Ass Crust
A derogatory term used to describe anyone who pisses you off. Derived from the leftover pieces of shit left in your ass after the umpteenth swipe.

Not to be confused with asshat.
Student A: What'd you get on the science test?
Student B: 64. Mr. Bober's a dick.
Student A: Really? I thought it was easy; I got a 110!
Student B: *glares* You cocky ass crust. Piss off.