Cersei Lannister is in Harry Potter.
Cersei Lannister is a fictional character in the A Song of Ice and Fire series of fantasy novels by American author George R. R. Martin , and its television adaptation Game of Thrones , where she is portrayed by Lena Headey . Introduced in 1996 's A Game of Thrones , Cersei is a member of House Lannister , one of the wealthiest and most powerful families in the kingdom of Westeros .