Character Arc
Cersei Lannister is the queen consort of King Robert Baratheon and twin sister of Jaime Lannister, with whom she maintains a secret incestuous relationship. Beautiful, ambitious, and ruthless, Cersei has been shaped by a lifetime of being underestimated and controlled by men in a patriarchal society. She genuinely believes she would have been a great ruler if born male, and much of her cruelty stems from a desperate need to seize the power that was always denied her by virtue of her gender.
Cersei's defining trait is her fierce love for her children — Joffrey, Myrcella, and Tommen — whom she sees as extensions of herself and her claim to power. A prophecy from the witch Maggy the Frog haunts her: that all her children will die and a younger, more beautiful queen will cast her down. This prophecy drives her paranoia and increasingly erratic behavior as she watches it come true one child at a time.
After the death of her last child Tommen, Cersei seizes the Iron Throne for herself, having destroyed the Great Sept of Baelor with wildfire to eliminate the High Sparrow and her enemies. As queen, she rules through fear and manipulation, refusing to send her armies north to fight the White Walkers and instead plotting to consolidate her own power while her rivals exhaust themselves.
Cersei's end comes not through dramatic confrontation but through the collapse of the Red Keep during Daenerys's attack on King's Landing. She dies in the arms of Jaime beneath tons of rubble, terrified and vulnerable — stripped of her crown, her power, and her defenses in her final moments.