A bastardization of the word ketchup, for people who like to garnish their burgers and dogs and swear at the same time. Goes well with mouseturd.
Cecil: Hey! Ya got any katshit or mouseturd for these here burgers?
Gloria: <sigh> What are you, four? Can't you even speak without swearing?
Cecil: <rolls his eyes> Tse, I'm just kiddin', for fuck's sake! ... so do ya got any or what?