When you're really turned on and disgusted at the same time, and jizz/puke out of your mouth.
Coined by the College Humor staff in their video Juke as part of their All Nighter: III
Dan: "I juke whenever I watch two girls one cup"
Matt: "So do I! I mean the girls are so hot, but its so disgusting at the same time... its hard not to juke"