Cersei is the widow of King Robert Baratheon and Queen Regent of the Seven Kingdoms. She installed her son Joffrey Baratheon on the Iron Throne under the false claim that he was a legitimate son from her marriage but he was actually the product of her incestuous relationship with her younger twin brother Ser Jaime Lannister.
Cersei is the only daughter and eldest child of Joanna Lannister and Lord Tywin Lannister. Tywin is the head of House Lannister, the richest man in the Seven Kingdoms and Lord Paramount of the Westerlands. The Westerlands are one of the constituent regions of the Seven Kingdoms and House Lannister is one of the Great Houses of the realm. Cersei is the elder twin of Ser Jaime Lannister and the elder sister of Tyrion Lannister. She was raised in privilege in the family seat of Casterly Rock. She is noted for her great beauty.
Cersei's mother died when she was four years old, after giving birth to her younger brother Tyrion. Like her father, Cersei has always blamed Tyrion for her mother's death and deeply resents that her mother died so that Tyrion would be brought into the world. Cersei's father Tywin was constantly away from home during her childhood and teenaged years, serving as Hand of the King at the capital, with only infrequent visits back to his seat at Casterly Rock. Coupled with the death of her mother, this meant that Cersei and her two brothers were primarily raised by servants attached to House Lannister. She began an incestuous relationship with Jaime in her youth which has continued despite her marriage. Cersei has had other partners but Jaime has always been faithful to her.
She is the wife of King Robert Baratheon, a political marriage Robert agreed to in thanks for her father's late switching of sides in the civil war which brought him to power. She was aged 19 when she married Robert and became Queen. She has three children: Joffrey, Myrcella and Tommen. She claims that they are Robert's although they are actually illegitimate and a result of her relationship with her brother Jaime, which is not common knowledge.
In King's Landing, Queen Cersei watches the silent sisters preparing the body of Lord Jon Arryn, the Hand of the King, for burial. She and her twin brother, Jaime, discuss the situation and wonder if Jon told anyone else about what he had discovered. Jaime tells her not to worry, since if the King knew the truth they'd be dead already. She suggests that Jaime could be the next Hand, but Jaime refuses, citing the position as too much responsibility and danger.
King Robert decides to travel to Winterfell and ask his best friend, Lord Eddard Stark, to become the new Hand, as well as proposing that his son Joffrey marry Eddard's eldest daughter, Sansa. Cersei, Jaime, and a retinue of courtiers accompany him. When the royal party arrives at Winterfell (the seat of House Stark) Lord Eddard presents his household to Robert and Cersei. After initial greetings, Robert demands to see the crypts and pay his respects to his former betrothed, Lyanna Stark, stoking Cersei's impatience. After Robert and Eddard depart, Cersei sends Jaime to find their younger brother Tyrion, who has become distracted at the local brothel.
That evening a great feast is held and Cersei and Catelyn Stark exchange cordial words. Cersei seems impressed by Sansa, thinking that she will be a great hit at court. The next morning Eddard and Robert go hunting, leaving the castle largely empty. Cersei and Jaime liaise in derelict tower. Bran Stark climbs the tower and finds them engaged in sexual intercourse. He is caught watching by Cersei, and Jaime grabs him. He asks how old Bran is. When Bran replies "ten", Jaime sighs and pushes him out of the window, musing "the things I do for love."
A month later, at breakfast, Tyrion tells his family that Bran is expected to live and notes his sibling's guarded reactions to the news. Cersei visits Catelyn who is sitting vigil for Bran. Cersei tells Catelyn that her first child, a beautiful, black-haired boy, died because of a fever. She and Robert were grief-stricken and her prayers and tears were for naught. She offers to pray for Bran's survival, hoping that this time the gods will listen. The royal party sets out for King's Landing, now joined by Eddard, Sansa and Arya. However, a minor fracas between Arya's direwolf and Joffrey on the Kingsroad escalates into an argument between Cersei and Eddard. Robert defuses the situation by agreeing that he and Eddard will attend to their own discipline. Cersei insists that the direwolf must be killed. When Nymeria cannot be found (Arya having driven her off to protect her), Cersei has Sansa's wolf, Lady, killed instead. Eddard, furious, attends to the matter himself.
Arriving back at court, Cersei talks to Joffrey about the incident on the Kingsroad. She tells him that when he is king, the truth will be whatever he decides it will be. Joffrey tells her that he thinks there will be trouble with the Starks, and that when he is king he'll double their taxes, force them to contribute to a standing army and, if they should object, he'd crush them. Cersei elucidates that the North is too vast and wild to be militarily conquered by outsiders. She cautions Joffrey that he will need to be cleverer as king. She also advises him to be kind to Sansa to avoid storing up trouble for later, and concludes that "anyone who isn't us is an enemy." A raven arrives in King's Landing with news of Bran's recovery. Cersei fears he will expose their secret, but Jaime comforts her.
Cersei and Robert share a drink and discuss the threat from the Dothraki now that Daenerys Targaryen is married and pregnant. Cersei also tells Robert that at the start of their marriage she truly loved him. He says he knows, but could never love her back due to his feelings for Lyanna Stark.
Cersei and King Robert visit Eddard as he recovers from wounds sustained fighting Jaime and his guards. Cersei is furious with Eddard for having her brother Tyrion arrested and for fighting with Jaime, but Eddard is unrepentant.
Eddard confronts Cersei and tells her he knows her children are fathered by Jaime. She does not deny it, instead saying that she and her brother belong together, always. Cersei says she did love Robert, at the start, but on their wedding night he uttered Lyanna's name, which soured their relationship afterwards. Eddard advises her to leave King's Landing before Robert returns from a hunt, as he will then tell Robert the truth. Cersei instead warns him that "In the game of thrones, you win or you die."
Robert is mortally wounded on the hunt. Cersei is concerned that Eddard will tell Robert the truth, but Eddard chooses to spare his friend further pain. Robert names Eddard Protector of the Realm and regent. Upon Robert's death Cersei quickly installs Joffrey on the throne. Eddard tries to reveal the truth with the help of Petyr 'Littlefinger' Baelish, but Baelish betrays him and sides with Cersei. Eddard is arrested and imprisoned, whilst his guards are killed.
Cersei persuades Sansa to write a letter asking her brother Robb to bend the knee to Joffrey in return for her father's life. Sansa agrees, but the plan backfires, as the letter merely encourages Robb to raise an army and march into the Riverlands to confront the Lannister armies directly. In open court, Cersei encourages Sansa to make a new plea to Joffrey for her father's life. Joffrey agrees to spare him and let him join the Night's Watch, if Eddard recants the claims he has made about Joffrey not being the true king. Sansa is sure he will. Cersei is present at the Sept of Baelor when Eddard Stark 'confesses' his crimes, as per their arrangement brokered by Sansa and Varys. She appears to be genuinely shocked when Joffrey ignores the arrangement and demands Eddard's decapitation. The order is carried out by Ser Ilyn Payne, the royal executioner.
War erupts between the Lannister and Stark armies in the Riverlands and Cersei attempts to secure her son's hold on the Iron Throne. She takes a new lover, her cousin Lancel who was King Robert's squire and gave him the wine that made him too drunk to slay the boar that killed him. She also receives a letter informing her of Jaime's capture by Robb Stark.
Cersei continues to govern from King's Landing as the Queen Regent to Joffrey. She is driven to defend Joffrey's claim in the face of several challengers in the War of the Five Kings. Facing imminent winter she orders the city gates barred to prevent further refugees from entering the city. She is perturbed by the arrival of her brother Tyrion who has been named acting Hand of the King by their father Tywin Lannister. She fears that Tyrion schemes to usurp her power and is frustrated when he tells her that since she failed to prevent the death of Eddard Stark she has been viewed as the disappointing child by Tywin. Tyrion wins her temporary acceptance when he pledges to free Jaime from captivity but insists that they need to recover the escaped Arya Stark to facilitate a prisoner exchange.
Stannis Baratheon sends copies of a letter detailing Cersei's incestuous relationship with Jaime and the illegitimacy of her children to high lords throughout the seven kingdoms fuelling widespread rumors. Cersei tasks Petyr Baelish with recovering Arya and is enraged when Baelish dares to reference the rumors. She asks Joffrey to enlist the aid of Tywin in the search but he refuses to involve his grandfather. He provokes an argument with Cersei about the rumors and threatens her life when she slaps him. He then orders a citywide massacre of Robert Baratheon's bastard children.
Cersei rejects King Robb Stark's peace terms and refuses a request for aid from the Night's Watch, ignoring news of wights attacking the Lord Commander. Tyrion ousts Lord Janos Slynt as commander of the city watch for his part in the massacre as well as his betrayal of Ned Stark. Cersei angrily confronts him for displacing her loyal servant. He warns her to consider the importance of the support of her subjects; she is dismissive of his concerns but becomes upset at the weight of responsibility she has born. Tyrion mocks her relationship with Jaime. She ends the discussion by saying that Tyrion's finest joke was killing their mother when he was born.
Tyrion tests the loyalty of the remaining small council members by feeding each of them a different marriage plan for Myrcella. Pycelle dutifully informs Cersei of Tyrion's plans to marry Myrcella into House Martell of Dorne despite his promise to keep them secret. Cersei confronts Tyrion who insists that the alliance is necessary and that Myrcella will be safer in Dorne. He then has Pycelle arrested for breaking his confidence. Tyrion sends Petyr Baelish to treat with Catelyn Stark leaving Varys as the last member of Cersei's small council in the city. Robb Stark wins a major victory at the Battle of Oxcross. Joffrey responds by having Sansa Stark publicly beaten, sparing her only because of Cersei's orders, that if Sansa is killed the Starks will exact vengeance on his uncle Jaime. Tyrion intervenes causing further deterioration in his relationship with Joffrey.
Cersei issues a warrant demanding the release of Pycelle. She tasks her lover and cousin Lancel Lannister with delivering it to Tyrion. Lancel arrives in the middle of the night, Tyrion asks why he waited so long to deliver the message. When Lancel says he just came from Cersei. Tyrion noticing Lancel smells of Cersei's perfume, threatens to exposing their relationship to Joffrey, unless Lancel agrees to become Tyrion's spy reporting everything Cersei does.
Cersei is pleased when she learns of King Renly Baratheon's death. Tyrion considers it a sign of an imminent attack by his brother King Stannis Baratheon, who has assumed control of Renly's army. Cersei refuses to discuss measures for the defense of the city and remains irate about the marriage pact with Dorne. Tyrion learns from Lancel that Cersei is relying on the Alchemists' Guild to supply Wildfire to defend the city and subverts her relationship with the Alchemists' Guild.
Cersei and the court assemble at the shore of the Blackwater Bay for the departure of Princess Myrcella. Cersei remains livid about Tyrion's arrangements for her daughter. She threatens to one day deprive him of someone he loves. As they move through the city to return to the Red Keep they are confronted by angry crowds of starving smallfolk. Joffrey is hit by thrown excrement and triggers a riot by demanding that his guards kill everyone in the crowd. Tyrion marshals the Lannister guards to lead them to safety.
Cersei learns that Sansa has flowered for the first time, she summons Sansa and offers her advice on motherhood. Cersei tells her to love only her children, since love makes you weak, but it is a mother's obligation to love her children. Sansa asks if she should love Joffrey; Cersei replies that she can try.
Cersei meets with Tyrion to discuss the imminent attack of King's Landing by King Stannis Baratheon. She admits her struggles controlling Joffrey and openly references her relationship with Jaime. She confides her fear that Joffrey's madness is the price for her sins, including her incestuous relationship. Tyrion tries to comfort her by telling her that Tommen and Myrcella are good, decent children.
Joffrey is keen to fight in defense of the city. Cersei is furious and suspects Tyrion of trying to kill her son. She mistakenly identifies Ros as his lover because of the Lannister necklace Tyrion gave her and seizes the opportunity to deliver on the threat she made when Myrcella left. Cersei has the prostitute kidnapped as insurance against Tyrion placing Joffrey in harms way. She reveals her ploy over dinner and Tyrion vows to free Ros and take revenge when Cersei least suspects it.
Cersei provides refuge for the women of the court in Maegor's Holdfast during the battle. She prepares for the worst by having Ser Ilyn Payne present and obtaining deadly Essence of Nightshade poison from the reinstated Pycelle. She drinks heavily during the siege and torments Sansa Stark when she tries to keep up the morale of the women by praying. She tells Sansa that the gods have no mercy and that Ser Ilyn is there to kill them should the Red Keep be breached. Lancel is wounded and returns from the walls to report that Stannis has reached the Mud Gate despite Tyrion's ingenious use of Wildfire to destroy a portion of his fleet. Cersei sends Lancel to bring Joffrey back to the Red Keep, ignoring his protests that it will damage morale. Joffrey willingly leaves the field but his exit is a blow to the men. Lancel begs Cersei to let him return Joffrey to the front, believing the battle is lost otherwise. Cersei pushes him into a stone pillar, aggravating his injury, and storms out. Convinced the battle is lost, and not wanting her children to die by Stannis's hand, she takes Tommen to the Iron Throne room and prepares to poison him. She is stopped just in time by the unexpected arrival of Tywin, who reports that they have won the battle. Tyrion is betrayed and wounded by Ser Mandon Moore of the Kingsguard during the fighting. Tyrion's role in defending the city is not acknowledged and he is left to recover from his wounds, stripped of his power. Rumors circulate that Cersei ordered the attack on Tyrion. No longer considering Tyrion a threat, Cersei releases Ros.
Cersei orchestrates a public ceremony rewarding those who aided the city in the battle. Tywin is officially recognized as Hand of the King, Petyr Baelish is named Lord of Harrenhal for brokering the alliance with House Tyrell and Ser Loras is offered a favor of his choosing. He asks Joffrey to marry his sister, Margaery Tyrell. Joffrey says that he is constrained by his betrothal to Sansa but Cersei intervenes to insist that the treachery of House Stark frees him from any obligation. The court welcome the decision with a round of applause.
Some weeks after the Battle of Blackwater, Cersei pays Tyrion a visit accompanied by two of her son's Kingsguard. She only gains entrance to Tyrion's chambers after agreeing to leave her guards outside. Once inside Cersei demands to know how he will "slander" her to their father now that he is here. Tyrion asks when he has ever slandered her before, and she reminds him of a time at Casterly Rock that he got her in serious trouble with their father: when she was nine years old, Cersei discovered that a servant girl (also nine years old) had stolen a necklace, so she had her guards beat the girl, who ended up losing an eye. Tyrion told their father what Cersei'd done and he was angered, but Cersei notes that the servant girl never stole a necklace again. Tyrion quips that it isn't "slander" if it's true, and he only told Tywin what she really did. The queen admits that Tyrion is a clever man but not as clever as he might believe. Tyrion merely retorts that this still makes him a great deal more clever that her. Cersei then leaves abruptly and just in time to prevent Meryn Trant and Bronn from exchanging blows.
At night Cersei and Joffrey are hosting a private dinner party for Loras and Margaery Tyrell. Cersei is surprised that Margaery has been handing out food aid to the smallfolk of the city and visiting orphanages. Unlike Cersei, who only knows how to rule through fear, Margaery is skilled at manipulating the people into loving her, and this concerns Cersei. After trading veiled insults with both her son and future daughter-in-law it becomes clear that Cersei doesn't trust Margaery and fears that the younger woman has come to supplant her as queen.
As the court gathers for Tyrion's wedding, Cersei finally snaps when Margaery says she looks radiant. Cersei reminds the queen-in-waiting of the lyrics of The Rains of Castamere and to take a lesson of what happened to House Reyne. Cersei threatens to have Margaery strangled in her sleep if she ever refers to her as "sister" again. Cersei maintains a cool expression during the ceremony, and does not laugh when Joffrey ridicules Tyrion by removing his footstool. During the wedding feast, Joffrey heads off to torment Sansa some more. Fed up with him, Cersei tells him to speak with Margaery instead, but he ignores her. Cersei later retreats to an upper gallery and stares despondently out over Blackwater Bay. Loras sees her and tries to make small talk, but Cersei rudely brushes him off.
Cersei is present at the meeting where Tyrion learns of Robb and Catelyn's deaths. Joffrey comments that he wants Robb's head to present to Sansa at his wedding feast, though Varys reminds him that Sansa is now his aunt-by-marriage. Cersei brushes this off as a joke, though Joffrey denies this. She also reassures Joffrey when he is threatned by Tyrion. She also leads Joffrey to bed after he calls Tywin a coward.
Later, Cersei visits Tyrion and rudely dismisses Podrick. She tells Tyrion that he should give Sansa a son if he truly wants to make her happy, though Tyrion responds by asking her if she is happy as she has children. Cersei admits that she is not happy, but would've thrown herself "from the highest window in the Red Keep" without them, even Joffrey. She recounts of how he was all she had before Myrcella was born and how she would spend hours looking at him, and acknowledges that he is one of the "terrible ones". Tyrion asks her when this will end, and Cersei replies when they have dealt with all their enemies. Tyrion mentions how dealing with one enemy creates two more, and she just says that they will be in this position for a long time.
When Jaime returns to King's Landing, he immediately goes to Cersei's chambers and calls her name. She turns around, shocked and sickened at finding him maimed.
Cersei is present whilst Qyburn is attaching Jaime's golden hand that she commissioned for him because she's so disgusted by his stump. After Qyburn departs from Cersei's chambers, Jaime asks why she drinks more than she used to. Cersei replies that she drinks more because Jaime left the capital, Robert was killed, Myrcella was shipped off to Dorne, they went through a siege, and her son Joffrey is being married to Margaery whom she despises. When Jaime tries to make love to her, she refuses him and says that everything has changed and that he took too long reaching King's Landing.
Cersei is present at the breakfast of Joffrey and Margaery and tells Tywin about Shae being seen leaving Tyrion's chambers. During the Royal Wedding , Cersei sits with the rest of the royal family. When Brienne of Tarth approachs the king and Margaery, she bows and congratulates them on their marriage. Cersei quickly points out that she bowed instead of performing a courtsey. She then thanks Brienne for bringing her brother back and asks her if she loves Jaime, Brienne responds by walking off.
After Margaery says that the leftovers were going to the poor, Cersei kisses her on the cheek and says she is an inspiration to them all. Shortly after that she goes over to Pycelle , who is talking to a young woman, Cersei tells Pycelle to leave her alone and says that she should get Qyburn to examine her. Pycelle mocks Qyburn but Cersei responds by ordering Pycelle to go to the kitchens and order the cooks to give the leftovers to the dogs. Pycelle is reluctant to do so, but Cersei threatens to have him killed if he does not. Cersei and Tywin meet Oberyn and Ellaria and the four get into a heated discussion. When Joffrey is dying, Cersei rushes over to her son and is in tears when he dies. In a blind rage, she has Tyrion arrested.
Cersei is mourning Joffrey while Tywin arrives and immediately begins instructing Tommen on the qualities of a good king. After the two leave, Jaime arrives to comfort Cersei. She breaks down into tears and asks Jaime to avenge their son by killing Tyrion. Jaime is not convinced that Tyrion was behind the murder and tells Cersei that there will be a trial, but she does not care. He tries to comfort her through his affections. Cersei refuses initially, but Jaime is aggressive. Cersei insists that the sept during a private viewing of their son's corpse is a highly inappropriate place for sex, and asks Jaime to stop, saying "It isn't right, it isn't right..." and Jaime refuses to stop, saying, "I don't care, I don't care...". They then have sex next to their dead son's corpse..
Cersei calls Jaime to his chambers, but only to know about Kingsguard formations for protecting Tommen. She then asks why Catelyn Stark released him from his captivity. Jaime replies that he swore by all the gods that he would bring back Catelyn Stark's daughters to her. Cersei questions his loyalty to their enemies, but Jaime states that he only did it so he could return to her. She then asks if he could track down and kill Sansa Stark, believing that she schemed with Tyrion to murder Joffrey. Jaime remains silent. He then tries to convince Cersei that Tyrion is innocent, but she refutes that he has always pitied their little brother and firmly believes that Tyrion is the monster that killed their son. After, Cersei asks him to leave, but refers to him as "Lord Commander", showing that their relationship has almost completely deteriorated.
Cersei is present at the coronation of her son, Tommen. Seeing Margaery at the coronation, Cersei tells her that she understands that Joffrey was a monster, but as her first child, Cersei still loved him. She also believes the newly crowned Tommen will make a good and decent king, but he needs guidance. Cersei asks Margaery if she is still interested in being queen. Margaery says she will need to speak to her father about the matter.
Cersei is present at a small council that discusses the threat of Daenerys Targaryen, who they learn has recently conquered Meereen. Cersei doubts that Daenerys is credible threat the Iron Throne, a view not shared by the rest of the council. When Varys mentions that Sandor Clegane has been spotted in the Riverlands, Cersei recounts him as being both a coward and a traitor to the crown.
At Tyrion's trial, Cersei is verbally confronted by Tyrion, who angrily declares his innocence, but tells her how he wishes he could have been the one to murder Joffrey and that he felt the boy deserved it. Cersei approaches Gregor Clegane and enlists him as her champion in the trial by combat for Tyrion's fate. She watches proudly as he defeats Tyrion's champion, Oberyn Martell, and smiles as their father sentences Tyrion to death. She later sees to the treatment of Ser Gregor's wounds.
Cersei confronts her father and defiantly asserts once again that she will not consent to marry Loras Tyrell. When Tywin insists, she shocks him further by confirming for the first time to his face that the rumors about her relationship with her twin brother are in fact true. Disgusted, she leaves Tywin's quarters and proceeds to find Jaime. Though they still disagree on the fate of their younger brother, she approaches Jaime and kisses him passionately. She reaffirms her love for him and her wishes to continue their relationship regardless of what others may say. She kisses his gold hand as a symbol of her acceptance, and he makes love to her.
Escorted by Ser Meryn, Cersei walks to the Great Sept of Baelor for Tywin's funeral, surrounded by numerous lords and ladies, including Margaery, who she glances at suspiciously. Cersei is stopped by the High Septon, who suggests to her that they start soon, since lords and ladies have come from all over Westeros, but she says they will wait a little longer while she has a moment alone with Jaime and their father's corpse. Inside, Jaime warns that all the power and prestige their father built for House Lannister belongs to them now, and that, once everyone sees that Tywin is truly dead, their enemies will do everything they can to take it away from them. Cersei bluntly states that their true enemy is Tyrion and that Jaime is partly responsible for Tywin's death since he was the one who released their father's murderer, and then she leaves him. Later, during Tywin's wake, Cersei is approached by Loras, who babbles on and on, but she ignores him, as she is intently watching Tommen and Margaery sharing a few words and holding hands. Pycelle offers his condolences, yet she completely ignores him as well. She is then approached by Lancel, who has recovered from his wounds at the Blackwater and become extremely pious and joined the Sparrows. Kevan apologizes for the appearance of his son, but Cersei comforts him by saying Lancel will grow out of this phase. While she is having a private moment, Lancel approaches her again and asks for her forgiveness for their "unnatural" relationship, and for serving Robert the wine that led to his death. Cersei brushes off Lancel's request, and his prayers for Tywin's soul.
Cersei summons Jaime to show him a box she's received. Inside, a stuffed Red Viper holds Myrcella's necklace in its jaws. Cersei is both unnerved and unsurprised by the threat Dorne blames the Lannisters for the deaths of Oberyn and Elia Martell. Acknowledging Cersei's distress, Jaime makes a promise: "I'm going to Dorne. And I'm bringing our daughter home." When Jaime goes to look for Bronn to take him in this quest, he reveals that Cersei has arranged for Willas Bracken to wed Lollys Stokeworth instead of Bronn, breaking their agreement.
Later, two men bring Cersei the head of a dwarf. She's disappointed it's not her brother, but donates the head to Qyburn's lab. Cersei presides over the Small Council and doles out new titles on Tommen's behalf: Qyburn is named Master of Whisperers, and Mace Tyrell takes on the additional title of Master of Coin. When Cersei appoints her uncle Kevan as Master of War, he rejects the offer. "I did not return to the capital to serve as your puppet," he says, emphasizing that Tommen should attend the meetings himself. Kevan reminds Cersei she's nothing more than Queen Mother, and he decides to return to Casterly Rock. Cersei is left dissatisfied with Kevan's departure.
In her litter on the way to the Sept of Baelor, Cersei is incensed to find the crowd cheering Margaery's name. She remains stone-faced throughout the ceremony. The following morning, Cersei walks with Tommen along the battlements and tries to subtly turn him against his wife, but Tommen scares her by asking her if she'd prefer to go back to Casterly Rock. Cersei goes to confront Margaery, finding her bragging about Tommen's libido to her handmaidens. Cersei tries to verbally spar with Margaery as she used to, but the younger queen is in her prime, and assaults Cersei with backhanded compliments subtle barbs. Realizing that she is losing, Cersei departs. Later on, Cersei and the Small Council are visited by the High Septon, who has recently been abducted from Littlefinger's brothel and forced to walk naked through the streets of King's Landing. Cersei is mildly amused and not particularly sympathetic to the man's plight. She later pays a visit to the so-called High Sparrow. Assuming a much more conciliatory and humble tone than she ever has before, Cersei talks with him about the relationship between the Faith and the Crown... and also mentions that she's had the High Septon thrown in the Black Cells.
Cersei meets with the High Sparrow again and names him as the new High Septon, allowing him to reinstate the Faith Militant, a military order dedicated to defending the Faith of the Seven which was abolished two centuries ago. Loras Tyrell is arrested during the ensuing rampage for his homosexuality, which Margaery believes is part of Cersei's plan to divide her and Tommen. Tommen confronts his mother and demands that Loras be released, but she calmly tells him that she didn't order his arrest, although her tone of voice seems to imply that she knew beforehand that Loras would be arrested and allowed it to happen in order to interfere with Margaery and Tommen's relationship.
During her meeting with Littlefinger Cersei again feigns ignorance about Loras' arrest and seems unconcerned about what repercussions this might have. The Queen Regent is about to dismiss Baelish when he admits that eventhough he lost track of Arya, he has discovered Sansa Stark's whereabouts. She's back at Winterfell 'allying' herself with House Bolton.Cersei is natuarally livid that the Boltons have betrayed her and vows that they'll end up being flayed for their crimes. Petyr then suggests that Cersei could just wait a while until Stannis has dealt with the Boltons or vice versa. The Vale army (under his command) could later easily mop up the remains. The only boon Littlefinger wants for his service is to be named Warden of the North. Cersei readily agrees on the condition that Bailish brings her Sansa's head.
After a brief but tense meeting with Olenna in wich mutual insults are exchanged, Cersei takes part in the trial of Loras Tyrell. Though she appears incredulous towards the accusations, it is clear that she has played a part in engineering the entire process. She plays the same trump card that she once did with Tyrion and Shae by making a deal with Olyvar, Loras's lover, to testify against Loras in exchange for being spared from persecution. As a result of her schemes, Loras is to be put on trial, and Margaery is imprisoned for giving false testimony.
When Tommen loses his appetite over his wife's arrest, Cersei attempts to calm him down, and gives him a long speech about how as King, he will be faced with many circumstantial situations in which he will be powerless to act, as Robert Baratheon sometimes was, though she proclaims her love for him by claiming that she will do anything it takes to protect him, even if it means burning down entire cities, and weeps as she cuddles her son. She later visits Margaery in her cell, bringing her food and trying to convince her that she will do her utmost to get her out, but Margaery angrily counters that she knows Cersei engineered both her arrest and Loras's in order to retain control over her son, and shouts at her to get out, throwing the bowl of stew at her and calling her a "hateful bitch". Cersei leaves and finds the High Sparrow beneath the Sept of Baelor, who tells her that both Loras and Margaery will both be put on trial, and certain septons, including himself, will stand as judges. Cersei thanks the High Sparrow for his actions, and he proceeds to give her a speech about the history of the Sept of Baelor. He tells her that the Tyrells' falsehoods will be revealed for all the world to see, as in the case of everyone, including Cersei herself. The High Sparrow reveals that Lancel confessed his adulterous affair with Cersei following Jaime's capture by Robb Stark, and orders Cersei arrested, to her horror. She is taken to a cell by a group of septas, but threatens them that her face is the last thing they will see before they die for what they are doing to her.
Cersei remains in custody for the next few days, visited only by Septa Unella, who offers her water in return for a confession, but she repeatedly refuses. She is later visited by Qyburn, who informs her that the charges against her are treason, incest and regicide, which she dismisses as lies, though Qyburn reminds her that the Faith will not depend on physical proof as much as the Crown does in her upcoming trial: even if she truly is innocent but the Faith believes her to be guilty, even without proof, she will be convicted. She asks about Jaime, but Qyburn claims there has been no response, and further tells her that Pycelle has summoned Kevan back to the capital and Tommen has fallen into a depression. Qyburn, however, tells Cersei that she can still confess, but she refuses. Before he leaves, Qyburn tells her that his work is progressing. Later, when Unella visits her again, Cersei offers to make her a Lady of the capital or have her killed, depending on whether or not she will help her. Unella pours her water on the floor and leaves. Cersei finally abandons her pride and licks the water from the dungeon floor, breaking into tears.
Sometime later, Cersei is brought before the High Sparrow to confess her sins. She confesses of adultery with Ser Lancel Lannister, but denies her incestuous relationship with her brother Jaime. She begs to be allowed to go to the Red Keep to see her son Tommen. The High Sparrow accepts but states that she has to stand trial. Cersei is brought to a cell where she is stripped naked and washed before her hair is cut short. She is brought outside were she has to walk naked through the streets of Kings Landing from the Great Sept of Baelor to the Red Keep as punishment. She is escorted through an angry mob who throw rotten food at her and humiliate her.
With bloody feet she makes it to the Red Keep. Upon entering the gates, Cersei finds her uncle Kevan Lannister, Grand Maester Pycelle and Qyburn waiting for her. Qyburn attempts to comfort her by covering her body with a cloak. Heavy footsteps are heard, and Qyburn introduces Cersei to the newest member of the Kingsguard: a 7-8 foot tall man in golden armor. Qyburn suggests Cersei to go inside to have a look at her feet, which are badly injured, when the huge knight lifts her up and carries her away.
Once again residing in the Red Keep, Cersei is alerted to Jaime's return and runs excitedly to the port to meet him, but her worst fears are realized when she sees a despondent Jaime standing alone on the boat, with a corpse behind him she immediately realizes is Myrcella's. Later, Cersei is comforted by Jaime in her quarters. Cersei finally admits to Jaime that she believes their childrens' deaths are destined according to Maggy's prophecy, since both Joffrey and Myrcella are gone and the only one left is Tommen. Jaime scoffs it off and promises Cersei revenge for all their enemies have taken from them.
A man in King's Landing brags about revealing himself to Cersei during her walk of shame. When the man leaves the crowd to urinate, the gigantic Kingsguard knight walks up behind him and brutally kills him by smashing his head against the wall before reporting back to Cersei. When Cersei attempts to leave for Myrcella's funeral with the Kingsguard knight in tow, a squad of guards blocks her path; their leader informs her that by order of the King, she is prohibited from leaving the castle, in the interest of her own protection. Cersei demands that they move, but the guards do not budge, even when Cersei's Kingsguard places a hand on his sword. Eventually, Cersei acquiesces and retreats to her chambers. Tommen later visits his mother to apologize for doing nothing when she was arrested and forced to walk through the streets naked, then asks her to teach him to rule. Moved, Cersei tearfully embraces her son.
Cersei and Jaime later visit Qyburn in his lab, where he has swayed some of Varys's little birds into his service, to Cersei's amusement. When Jaime asks Qyburn to order Gregor Clegane to slaughter the High Sparrow and the Faith Militant, Cersei claims it will not be necessary, since she has opted for a trial by combat and again named Gregor as her champion. She then orders Qyburn to place his spies all over Westeros to prevent any other Great Houses from benefiting from the Lannisters' disgrace. Cersei, Jaime and Gregor attend a Small Council meeting, but Kevan, Pycelle, Olenna and Mace Tyrell refuse to accept them, with Olenna coldly reminding Cersei that she is no longer Queen. When they defy the council and sit down, Kevan leads the council out, leaving Cersei alone with Jaime and Gregor.
A few days later, Cersei goes to speak to Tommen, only to find he is already being counseled by Pycelle. Despite the Grand Maester's claim that he is simply offering his wisdom to the King, Cersei coldly orders him to leave. Once alone, Cersei wishes to speak with Tommen in private, having missed the past several Small Council meetings. Tommen is anxious to fight the High Sparrow, since Margaery is still a prisoner, though Cersei reminds him of what the Sparrow forced her to do. Although Tommen knows his mother has always hated Margaery, Cersei claims the rivalry is unimportant, explaining that kings and queens must command respect, and the High Sparrow is little more than an idealistic anarchist using the Faith to achieve his goals. After Tommen reveals his conversation with the High Sparrow and knowledge of something important, Cersei presses him for information.
Cersei and Jaime attend another Small Council meeting, this time presided over by Kevan and Olenna. Though Olenna reminds Cersei she is not welcome, adding her repeated humiliations, Jamie defends his sister, revealing that Tommen has been talking to the High Sparrow about Margaery and Loras. Cersei points out the High Sparrow was expecting them to fight among each other, and before the trial, Margaery will perform her own walk of atonement, which Olenna agrees must not happen. Although Cersei promises to destroy the Sparrows for corrupting Lancel, Kevan warns them the High Sparrow has many supporters, and more lives could be lost in the ensuing battle.
After his failure at the Sept of Baelor and forced removal from the Kingsguard, Jamie informs Cersei he is being sent to Riverrun to help the Freys deal with Brynden Tully. Despite her brother's protests, Cersei advises him to lead the Lannister army as their Father intended, confident that the Mountain will win her trial by combat. She kisses Jamie goodbye, reminding him they are the only ones who matter.
Cersei visits Olenna Tyrell in an attempt to convince her to stay in King's Landing. She uses Margaery and Loras as an excuse for Olenna to stay, but Olenna reminds Cersei that all this is happening because of Cersei herself. Olenna reminds her of the smug look she gave her when Loras and Margaery were being dragged away by the Faith Militant. She tells Cersei that the universally hated Queen Mother has no friends or support in King's Landing, and has truly lost.
Qyburn enters Cersei's chamber to inform her that the Faith Militant have entered the Red Keep. Accompanied by Qyburn and the Mountain, Cersei confronts the group. Lancel tells her that the High Sparrow wishes to speak with her at the Sept of Baelor. When she refuses, Lancel tells her that it is not a request. Cersei retorts that the High Sparrow promised that she could stay in the Red Keep until her trial, which Lancel replies that no such promise was made. When Ser Gregor Clegane threatens the Faith Militant, Lancel tells Cersei to order him aside or there would be violence. Cersei says that she chooses violence. One of the Faith Militant attacks the Kingsguard but his weapon does not penetrate the armor. In response, the Mountain rips the man's head off and tosses it aside and Lancel and his men back down.
Later, Cersei, Qyburn and Ser Gregor enter the Great Hall to find a large crowd gathered for a royal announcement. Cersei asks Kevan Lannister why she was not informed. Kevan bars her from standing beside her son and tells her that her place was in the gallery "with the other ladies of the court". Cersei reluctantly takes her place there while the other women stand aside, not wanting to be near her or Gregor.
King Tommen Baratheon starts by saying that the Crown and the Faith are the two pillars that hold up this world, and should one collapse, so does the other. He also says that The Father judges them all, and if they break his laws, they shall be punished. He announces that Loras Tyrell and Cersei's trial will be held in the Sept of Baelor on the first day of the festival of The Mother. After much prayer and reflection, he also announces that trial by combat will be forbidden in the Seven Kingdoms, stating that it is a scheme made by those who wants to escape true judgement from the Gods, and that Loras and Cersei would stand trial before seven septons as it was in the earlier days of the Faith.
As the King leaves, Qyburn tells a shocked Cersei, who had been planning on calling a trial by combat with Gregor as her champion, that his little birds have been investigating an old rumor that she had told him about, and that the rumor was found to be much more than a rumor.
On the day of her trial, Cersei dresses incredibly ornately. She is adorned with fine clothes and all manners of jewelry. However, she does not show up at the Great Sept for her trial, instead viewing the city in the distance from the Red Keep. Unknown to those present at the trial, there is a large cache of wildfire underneath the Sept, placed there by Aerys II at the height of his insanity. Cersei has Qyburn ignite the cache, and shortly before, has Pycelle assassinated, so as to consolidate all power to her. In the explosion, all the Sparrows, including the High Sparrow, Margaery, Mace Tyrell, Kevan Lannister, and Loras Tyrell, are killed
Following her coronation, Cersei shows Jaime a giant map of Westeros and discusses the multiple foes they now face. While Cersei has dreams of ushering in a long dynasty, Jaime reminds her that they are losing the war, and with all their children dead, there is no Lannister line to inherit the Iron Throne. When Jaime asks Cersei about Tommen, she responds angrily that he betrayed them by committing suicide. Cersei adds that they are the only living Lannisters who count. Jaime tells her that they need allies and reports that House Frey has been exterminated. Cersei angrily reminds him that she has been listening to their father's counsel for the past forty years and has learnt some things.
They later meet with Euron Greyjoy to discuss a possible alliance. Though Cersei declines his offer of marriage, Euron graciously departs, promising to return with a gift that will win her heart.
Euron returns to the capital with Ellaria and Tyene Sand, the women who poisoned her daughter Myrcella. Cersei has them both chained and gagged in one of the black cells. She tells Ellaria that even though they are enemies, she understands her captive's fury. She calls to mind how skillful a fighter Oberyn was up to the point when he got killed. She then reveals her own grief at losing her only daughter, and walks over to Tyene, complimenting her beauty before ungagging her and kissing her full on the lips with the very same poison that Ellaria used on Myrcella. Qyburn puts the gag back on Tyene and gives Cersei the antidote. Cersei tells Ellaria that she intends to keep her alive to watch Tyene die and rot in the cell, even if they have to force feed her.
She then expresses her delight by intimately engages with Jaime, after which she announces that, as Queen, she doesn't care if servants know of their incest. Then, Bernadette arrives, differing from the subject of Jaime, telling Cersei that Tycho Nestoris of the Iron Bank of Braavos has arrived. Following this she forms an alliance with Tycho, hoping that she will gain a loan after Jaime has successfully taken Highgarden. Tycho agrees to this possibility, as Daenerys has cost them many shares in wealth, due to her ending of slavery in the Slaver's Bay.
After the Sack of Highgarden, Cersei meets with Tycho in her atrium containing a large floor map of Westeros. Tycho is pleased that Cersei will use the captured gold to pay off the Iron Throne's massive debts to the bank, and he engages in open flattery by saying that she is as cunning at military strategy as her father Tywin was, if not more so.
Now that the Lannisters' old debts will be mostly paid off, and the Iron Bank's faith in them somewhat reassured by their recent military victories, Cersei wants to take out new loans to strengthen her position in the war, so she can finish securing control over the rest of the continent. They discuss that Cersei wants to use the money to hire foreign Sellsword companies to bolster the depleted Lannister military ranks. Specifically, she reveals that she has had Qyburn make overtures to hire the best and largest private mercenary army in all of the Free Cities: the Golden Company. Tycho assures her that the Iron Bank will be delighted to help her with these future endeavors, once it receives the gold she is bringing them.
Jaime returns to King's Landing to inform Cersei of their defeat in the Battle of the Goldroad. He flatly insists that the Lannisters have no chance of defeating Daenerys, even if Cersei were able to buy enough mercenaries to replace their huge losses; Qyburn's scorpion did little more than anger Drogon, and neither the Lannister soldiers nor any mercenaries will be able to match the huge horde of Dothraki, who Jaime notes killed their men as if it were sport to them, not war. Cersei snidely asks Jaime if they are expected to surrender to a Queen whose throne Cersei occupies and whose father Jaime betrayed and murdered, mockingly remarking that Tyrion could intercede for them with Daenerys.
Jaime reveals to Cersei that Tyrion is innocent of Joffrey's murder, telling her Olenna Tyrell confessed to it. Cersei is dismissive, so Jaime talks her through it, asking her rhetorically if Olenna would prefer Margaery to marry the strong willed and sadistic Joffrey or the emotionally pliable and good-natured Tommen. Effectively, Olenna would have become the true ruler of the Seven kingdoms behind the scenes - in the same way that their father Tywin Lannister became the true ruler of Westeros through his grandsons. Feeling cheated of yet another vengeance, Cersei can barely contain her fury as she laments listening to Jaime, saying Olenna ought to have died screaming.
Later, at the Red Keep, Qyburn is visiting Cersei when Jaime enters her chambers. Jaime tells Cersei that he met with Tyrion. When Cersei asks if Daenerys wants to negotiate a surrender, Jaime tells her that Dany is seeking an armistice due to the threat posed by the Army of the Dead. Cersei knows that Bronn secretly organized the meeting between Tyrion and Jaime. Cersei says that perhaps an alliance with Daenerys may be a wiser move, but she still retains her determination to destroy any force that stands against her. She also asks if Jaime plans to punish Bronn for arranging the clandestine meeting with Tyrion. She also reveals that she is pregnant with another of Jaime's children, one who she believes will someday be the heir to the Iron Throne. After reflecting on their late father's advice that "the lion does not concern himself with the opinions of the sheep", Cersei hugs Jaime and whispers in his ear that he is never to betray her again.
As the Parley in King's Landing comes into fruition, Qyburn tells Cersei from her chambers that Daenerys's forces are en route to the Dragonpit. Cersei then warns Gregor that if anything should go wrong, he should kill Daenerys first, followed by Jon and then Tyrion, following then in any order she sees fit, before departing herself.
At the Dragonpit, the various factions meet: Cersei, Jaime, Qyburn and Euron representing the Iron Throne, Jon, Davos and Brienne representing the North, and Daenerys' court. When Cersei demands to know where her rival is, the Dragon Queen makes a suitably dramatic entrance on Drogon's back, with Rhaegal flying overhead. Euron tries to posture, threatening to kill Yara unless Theon yields to him and deriding Tyrion's dwarfism; when Tyrion and Theon retort to his taunts with their own, Euron remarks that Tyrion would have been killed at birth in the Iron Islands. A furious Jaime orders Euron to sit down, and when he disregards the warning, Cersei reiterates it; a subdued Euron returns to his seat.
Getting the meeting on track, Tyrion, Daenerys, and Jon try to warn Cersei of the greater threat coming for them all, but she dismisses it as a ploy to trick her into lowering her defenses. To prove their claims, Sandor returns with the crate containing the wight, which is worryingly silent. Sandor gets the crate open, but there is still no movement. He finally gives the crate a massive kick, which prompts the enraged wight to launch itself out and charge toward the nearest target - Cersei, appropriately enough. Visibly horrified, the Lannister queen and her allies recoil in horror as Sandor pulls the wight back on a chain, its claws inches from Cersei's face, and manages to slice the creature in half when it turns to attack him. The assembled look on in shock as the wight's upper half still moves around. Jon steps forward and picks up the wight's discarded hand, using a torch provided by Davos to demonstrate how fire can be used to stop them. He then uses a dragonglass dagger to the heart to end the wight's upper half, bluntly stating that if they don't win the coming war, such a fate awaits every person in Westeros. A horror-struck Jaime asks how many wights are coming, and Daenerys tells him the army of the dead numbers at least 100,000. Euron asks if the wights can swim. When Jon responds, "No," Euron announces to Cersei his intention to withdraw the Iron Fleet back to the Iron Isles. He declares that he has been over the whole world and has never been terrified until now. On his way out, he tells Daenerys to retreat to her island while he returns to his own, and to come find him when they are the only two left alive.
Seemingly convinced, Cersei immediately offers terms: satisfied that Daenerys is concerned with the Army of the Dead, Cersei will not withdraw her troops, but will guarantee that they will not hinder the Targaryen or Northern forces in any way during the battle against the White Walkers. She refuses to deal with Daenerys at all, however, and calls on Jon Snow, as King in the North and Ned Stark's son, to keep the truce and to stay out of any future conflict between Cersei and Daenerys. Jon, however, says that he cannot serve two queens - and reveals to all assembled that he has already declared for Daenerys, infuriating all three Lannisters present. Declaring that there will be no truce if it is just her and Daenerys, Cersei storms out, content to let the Starks and Targaryens battle the undead alone and then deal with whoever emerges victorious from that conflict.
Tyrion later enters Cersei's office, and the two trade savage barbs. Although she finally acknowledges that Tyrion did not kill Joffrey, Cersei blames his murder of Tywin for the series of events that led to her younger children's deaths and the destruction of House Lannister's future. Tyrion maintains that he loved Myrcella and Tommen almost as much as Cersei and that he regrets what happened to them. He attempts to call Cersei's bluff, claiming that if Cersei genuinely blamed him for their deaths, then Gregor should just kill him right then and there. A tense moment passes in which Cersei does not give the order. Relieved, Tyrion heads straight for the wine. They continue their discussion until Tyrion realizes that Cersei is pregnant.
All three Lannisters then return to the Dragonpit. Cersei has agreed to work with Daenerys, but not by keeping her troops back: the Lannister army will march north to fight alongside the Starks and Targaryens.
After the enemy delegation has left, an eager and relieved Jaime meets with his commanders to discuss the logistics of moving the army north. Cersei enters the map room and asks what he is doing. Dismissing the commanders, she tells Jaime he really is the stupidest Lannister. Shocked, Jaime listens as Cersei explains that Euron has not abandoned her, but has gone to Essos to ferry the Golden Company back to Westeros. She intentionally leaked her pregnancy to Tyrion so he would believe her, and now she intends to allow their enemies to exhaust themselves against the Army of the Dead, then have the Golden Company mop up the remnants of whoever is left in the North. Jaime is furious that his sister and Euron plotted this behind his back, but Cersei angrily accuses him of plotting with Tyrion in favor of her enemies. Reeling from the accusation, Jaime incredulously reminds her that whoever wins the conflict in the North will turn their attention south afterwards; either the White Walkers will march south to kill them, or the Starks and Targaryens will come seeking revenge over the fact Cersei betrayed and left them (and essentially all of Westeros) to die, but Cersei is indifferent. Finally seeing his sister for the power-mad narcissist she truly is, Jaime disgustedly declares that he, at least, will fight to honor the pledge he made. When he tries to leave, he finds his way blocked by Ser Gregor. Cersei furiously insists that she will kill him as a traitor if he tries to leave, but Jaime calls her bluff and storms out, and Cersei does not give the order.
As she watches Jaime leave, both betrayed and saddened, snow begins to fall on her city, showing that winter has finally reached the South.
The only daughter of Tywin Lannister, Cersei was involved in an incesturous relationship with her twin brother Jaime even before she was married off to Robert Baratheon. Cersei’s plan to empower the Faith Militant backfired when she herself was imprisoned and accused both of murdering Robert and of incest - with her cousin Lancel. Cersei finally confessed to the one charge of incest, and as forced to atone by walking naked and in shame back to the Red Keep. Rather than face a trial, Cersei conspired with Qyburn to eliminate her enemies by detonating a secret cache of wildfire beneath the Sept of the Baelor. Her last living child killed himself after learning his wife died in the explosion. With no one to stop her, Cersei had herself crowned Queen of the Seven Kingdoms, and took her seat on the Iron Throne. Although she pledged Lannister troops in the fight against the Army of the Dead, she has no intention of keeping that promise. Jaime left the city upon hearing her deceit.
Cersei is willful, cold, ambitious, and cunning in the sense that she is utterly willing to betray anyone who trusts her, or do anything to protect her own. However, she is also arrogant and self-centered to a fault. While she certainly believes herself to be a master strategist, she is extremely impatient, short-sighted, and prone to displays of poor judgment, resulting in her being unskilled at manipulating enemies who openly distrust her. Cersei's own father Tywin stated to her that he distrusts her because she isn't nearly as intelligent as she believes herself to be. This makes for a dangerous combination, as not only is Cersei unintelligent, but she does not even realize her own limitations.
A mistake outsiders often make when dealing with Cersei is assuming that she has the emotional maturity and wisdom of a queen, or at least an adult, when her real personality is closer to a petulant child inhabiting an adult's body. In public, Cersei often tries to exude a sense of calm and regal control over her surroundings. When things do not go her own way, however, Cersei's usual response is to become extremely flippant, even when the assembled Small Council is trying to give her advice which would genuinely serve her own interests. Cersei's behavior is very mercurial, capable of switching between seemingly true affection for someone to extreme loathing over trifles.
As Tyrion noted, Cersei often uses her honest feelings to dishonestly manipulate other people. For example, her fear for the safety of her children is actually genuine, but she will shamelessly use this to play on the sympathy of other people, to sway them into supporting her.
Cersei despises the restraints placed on her because she is a woman and is jealous of the freedoms that men have in her society. Several of the noble Houses in the Seven Kingdoms have more liberal attitudes when it comes to involving female members of their family in politics. The women of House Tyrell, for example, are expected to be involved in politics and have thus been trained from a young age in the skills of ruling. Unfortunately, Cersei's father Tywin is a staunch conservative, and never envisioned Cersei playing an active role in politics. Instead, her duty was to cement a marriage alliance and raise royal children, nothing more. It is also possible that instead of her gender being the object, Tywin believes she is simply too impatient and rash. Either way, the practical result is that, right or wrong, Tywin didn't raise Cersei to be skilled in ruling or in political intrigue. While confronted with these shortfalls, Cersei often blames her father or society in general for not giving her the years of training needed to rule, but complaining about it doesn't change the fact that she simply doesn't possess these skills. Cersei hates being a woman in Westerosi society, and scorns other women in general for what she perceives as their weakness: Cersei isn't so much angry at men for mistreating women, as angry that she wasn't born a man.
Cersei's lack of a parental relationship growing up is reflected in how poorly she has served as a mother to her own children, for whom she is unable to act as a stable moral instructor. While she certainly dotes on them, she doesn't genuinely "love" them so much as she treats them as extensions of herself. She is convinced that she is obsessed with their welfare, but when events threaten to take any of them away from her she is not so much worried about their happiness and well-being as angered that something she feels belongs to her is being taken away.
Tyrion once observed that Cersei's love for her children is her one obvious redeeming quality - but she even managed to twist this into a negative. Cersei doesn't really "love" her children so much as she is obsessed with her mental constructs of them. She spent Joffrey's entire childhood convinced that he was going to grow up to be the best king ever, wise and brave - to the point that she blinded herself to his obviously psychopathic behaviour. However, in spite of her obvious favoritism and far from realistic conception of her son, she at least acknowledged that Joffrey was indeed a monster after his death, implying she wasn't as deluded as she appeared. Her overindulgence of Joffrey also spoiled him rotten, filling him with an insatiable sense of entitlement - nor did he particularly give her much respect in return. Meanwhile, Cersei seems oblivious to the fact that she ignored her two younger children, Myrcella and Tommen. While Cersei is constantly upset that her own father Tywin played favorites with his children and focused all of his attention on her brother Jaime, she hypocritically visited the same treatment on her own children. She fixated on Joffrey so much that she barely knew Myrcella and Tommen, rarely engaging them in conversation except when she needed to manipulate them. After Myrcella was sent away to Dorne in a marriage-alliance, Cersei assumed she was suffering away from her family, not suspecting that Myrcella would actually find happiness once she was free from Cersei's control and not even want to come back to her. After spending some years in Dorne away from her, Myrcella outright said that Cersei doesn't even know her. Finally, after the destruction of the Great Sept of Baelor, Cersei tells a captured Unella, she was motivated by protecting her last living child, Tommen. However, Cersei once again proves what a poor parent she is by not going immediately to Tommen after his wife is killed in the explosion and preventing his suicide as she was too preoccupied with paying back Unella for imprisoning and humiliating her.
After she was humiliated by the Faith Militant, the megalomania and vengefulness Cersei possessed all her life reached its peak. Combined with the rage she felt for her Uncle Kevan and the fact that Olenna Tyrell and Grand Maester Pycelle deprived her of power, Cersei began plotting with Qyburn to avoid her trial, simultaneously destroy her enemies, including the High Sparrow and Queen Margaery. This ended up destroying the alliance with the Tyrells, the only effective ally to King's Landing and a bloody revolt is to be expected by a vindictive Olenna. Cersei, however, does not seem concerned regarding this, displaying much more recklessness and slight mental imbalance on her part. Despite declaring herself Queen of the Seven Kingdoms, the title is effectively meaningless as currently the only major houses supporting her are her own and the Freys, although with the death of Walder Frey as well as the Freys' apparent military incompetence, they are unlikely to be useful allies. Along with the Lannisters now pitted against the rest of the great houses of Westeros, there is also the matter of the Crown's debt to the Iron Bank which has still not been resolved. So while Cersei might have achieved her ultimate ambition of being crowned Queen of the Seven Kingdoms, she is still in an incredibly precarious situation. However, this appears lost on her, further demonstrating her inability to see the far-reaching consequences of her actions.
Beforehand, Cersei was known to have an extremely thinly-veiled sense of morality, which can be attributed to her love for her own children, no matter how twisted it was. Now that Tommen, Joffrey and Myrcella are all dead, however, Cersei has begun displaying more ruthlessness and depravity in her convictions. Her use of wildfire to destroy the Great Sept of Baelor can be considered somewhat of a symbolic envoi to her own descent into the same level of tyranny as the the Mad King. This act also destroyed the area surrounding the Great Sept for half a mile, effectively murdering hundreds of innocent people. Ironically, this may serve to drive a wedge between her and Jaime; Jaime outright said that the only thing he cares about is Cersei and that he was willing to kill even children if it reunited them, but Cersei has committed an act similar to the one he had to kill the Mad King for. Jaime's grim look upon returning to King's Landing and witnessing her coronation means that he understands that she is becoming exactly like him.
Regarding her own crimes, Cersei appears to have become shamelessly sadistic. She outwardly admits that all her actions from having Robert killed to having an incestuous relationship with Jaime was solely because she enjoyed doing so. This, she "confesses" to a helpless Unella while vengefully playing with her, even quietly chanting "shame" (in a similar sense that Unella did during her walk of atonement) before leaving her to be tortured by Gregor Clegane.
All of this points to another mistake outsiders often make, Ned Stark for example, when dealing with Cersei as Olenna Tyrell noted before her death: failure to imagine just how far Cersei is willing to go to keep her power.