The act of tearing the vaginal wall during rough sex. Usually caused by a very clumsy or well endowed man.
Guy 1: So did you get with that girl last night?
Guy 2: Oh hell yea, I spent all night breaking the butterfly cage.
Guy 1: Wait, isn't that painful for her?
Guy 2: Who cares, I got laid!
Guy 1: SEX!
Guy 2: SEX!