House Lannister of Casterly Rock is a rich and powerful dynasty.
Their sigil is a golden lion on a crimson field, and their words are "Hear me roar!", but their unofficial motto, is "A Lannister always pays his debts."
Tyrion Lannister, is the son of Tywin Lannister. Tyrion is a dwarf, and is mockingly called The Imp or The Halfman.
Tyrion's is clever and calculating, but also one of the more sympathetic characters.
Cersei Lannister is the eldest child of Tywin and Joanna Lannister and the twin sister of Jaime Lannister.
After Robert's Rebellion she married Robert Baratheon, and became Queen of the Seven Kingdoms, but she is a Lannister through-and-through.
She is the mother of Joffrey, Myrcella, and Tommen Baratheon.
Jaime Lannister is the second child of Lord Tywin Lannister, twin of Cersei.
An exceptional swordsman, Jaime was raised to the Kingsguard at age 15, the youngest ever member.
He earned the derogatory nickname "Kingslayer" when he treasonously slew King Aerys near the end of Robert's Rebellion.
Joffrey Baratheon is the eldest son and heir of King Robert Baratheon and Queen Cersei Lannister.
Speculation regarding his real parentage is a key element of the story, given that all Robert's illegitimate children have his dark hair.
Sandor Clegane, nicknamed "The Hound", served as a bodyguard to Joffrey Baratheon, who would often refer to him as "Dog".
His face is disfigured from burns he received as child, when his older brother, Gregor, pushed his face into a brazier. He is a large powerful man, and a fierce fighter.