Baja Billy Goat
While doing a girl doggy style, as the man cums, he pushes as hard as he can to make the girls head come back. As her head comes back, the man immediately head butts her in the back of the head.
As me and my girl friend were having make up sex from our huge fight, I pulled the ole Baja Billy Goat to ensure that I got the last word and she got the head ache.