When you sing the pirates of the Caribbean theme tune and stick the whole of your forearm plus your fist up their bum hole and go ARGHH!
person 1: *sings theme tune*
person 2: dude, why you singing that?
person 1: *captin lizzies*
person 2: OUCH MAN THAT HURT
person 1: lol
person 2: * is in immense pain*
person 1: lol