A British term that means "in big trouble" or "trouble that will result in death" though the first one is more common.
This term isn't that commonplace in Britain anymore but still is used in extreme situations.
"You sir are in grave danger if you don't let me pass this door that leads in to the pub"
Ruler of Lake Titicaca. Rumored to have a bunghole that gets very angry if it does not receive toilet paper. Cornholio the Great is often seen walking around with his shirt over his head and his hands in the air, chanting songs about his power, and his bunghole.
"I am Cornholio! You do not want to face the wrath of my bunghole, for I need TP!"
Butthead: Shut up, Beavis! (uh huh huh huh)
Beavis: Um, okay. (heh heh heh heh).