Someone that goes and poops at a party to make everyone avoid the bathroom and to put everyone in a bad mood because all they can smell in the entire house in the stinky poop.
-Dude this party sucks, it smells like poop all over your house so everyonejust left or went outside.
-Yeah that was Craig who pooped in my bathroom downstairs.
-Yeah. Why would someone even poop downstairs? Is that sabotage? What a party-pooper.
Whilst this can be confused with the term 'Party Pooper', a slang term used to describe one who takes away the fun in a particular situation.
The 'Party-Pooper' is a prank that involves taking one's feces and placing it within an unused party popper. Once the party popper is pulled, the aforementioned feces is then shot out alongside the streamers.