House Lannister is one of the Great Houses of Westeros and the ruling family of the Westerlands. Their seat is Casterly Rock, one of the strongest castles in the realm, built above vast gold mines that made the family unimaginably wealthy. Their words are "Hear Me Roar!", though the unofficial saying most associated with them is "A Lannister always pays his debts."

The eldest child of Tywin Lannister and twin sister of Jaime. Proud, ambitious, and fiercely protective of her children. She secretly shares a lifelong relationship with Jaime, making him the true father of Joffrey, Myrcella, and Tommen. She constantly seeks power and sees Tyrion as both a threat and a source of bitterness within the family.

The eldest son of Tywin and Cersei's twin brother. A legendary knight known as the Kingslayer after killing King Aerys II. Behind his infamous reputation lies a man torn between honor, love, and duty. He is deeply devoted to Cersei and shares a genuine brotherly bond with Tyrion, unlike the rest of his family.

The youngest child of Tywin Lannister. Born with dwarfism, he lost his mother Joanna at birth and was blamed for her death by his father. Clever, witty, and highly educated, Tyrion survives through intelligence rather than strength. Jaime is the only close family member who truly loves him, while his relationships with Tywin and Cersei are filled with resentment.

The eldest child of Cersei Lannister and Jaime Lannister, though publicly known as the son of King Robert Baratheon. As heir to the Iron Throne, Joffrey is arrogant, cruel, and unpredictable. Raised to believe he is above everyone else, he rules through fear rather than respect. Despite his mother's constant protection, even his own family struggles to control him.

The second child of Cersei Lannister and Jaime Lannister, officially recognized as Robert Baratheon's daughter. Unlike most of her family, Myrcella is gentle, kind, and compassionate. She avoids conflict and has little interest in power or politics, making her one of the most beloved members of House Lannister.

The youngest child of Cersei Lannister and Jaime Lannister, though publicly believed to be Robert Baratheon's son. Kind-hearted, gentle, and eager to please, Tommen values peace over conflict. His soft nature often leaves him vulnerable to manipulation by those around him, especially his mother and influential figures at court.

Lord of Casterly Rock and head of House Lannister. Tywin is the father of Cersei, Jaime, and Tyrion. Ruthless, calculating, and respected across Westeros, he believes the family's legacy is more important than any individual. He trusts Jaime as his heir, uses Cersei for political gain, and despises Tyrion, blaming him for Joanna's death during childbirth.