Mr.Kitty is not commonly seen but there are some episodes about her. one from another site: "Wants whatever Cartman is eating, be it a chocolate chicken pot pie, corned beef cabbage, or beefy roast. Got singed by Cartman's anal probe when it persisted in meowing for his chicken pot pie and pissed him off. In the third season, Cartman calls him Mr. Kitty. Mr. Kitty turns out to be female, and in heat she goes looking for some action. She finds it and brings a lot of other cats home. An orgy ensues, with cats snorting catnip and drinking, passing out and having sex."
Cartman: Bad Mr.Kitty!