moonface
When someone passes out (or it could happen during kinky sex, you decide) and someone else (usually of the opposite sex) bends over and takes an enormous crap on the persons face while simultaneously rubbing their ass cheeks into it, creating a sludgy pool of human feces all over the persons face.
"Yo, Dean, what did you do with your new girlfriend last night?"

"Rob, I moonfaced that bitch!!"