Katy Perry is a famous American singer, songwriter, actress and guest star of The Simpsons. She appeared as herself in The Fight Before Christmas. She is divorced from Russell Brand, who also appeared as himself in the Simpsons. In the episode, Katy was the girlfriend of Moe, who, like the rest of the Simpson family, was a puppet in a parody of A Muppet Christmas Carol. She has released 3 albums and one video game. She also released a film, titled Part Of Me. Her best-selling single is Firework.