Somewhat like a Donkey Punch but since monkies have little hand-like feet, you kick the girl in the back of the head instead. Granted this would be hard to do, but I assume a monkey could do it no problem, hence name.
Matt H-Dude, I got monkey punched last night.
Everyone else-Dude, you got kicked in the back of the head while getting sodomized by another man? You suck.