Oh, and at one point, Gaga kisses Marge, so there's also that. Katy Perry was on "The Simpsons" and we could probably end this section here. But if you must know more details, the singer appeared ...

Katy Perry's music career started when she was still ... In 2010, Perry appeared in a Christmas episode of The Simpsons titled The Fight Before Christmas, taking the role of Moe Szyslak's girlfriend.