machine nut
A machine nut is when two guys, usually jocks or frat boys, try to cum as much as they can while sitting next to each other. The one who gives up first is a total loser, and the winner gets to shove his junk up the loser’s butt until he cums inside him.
Bro, I did six machine nuts before lunch. My butt is sore.
I lost a machine nut bet. Now he’s gonna stick his dick in my butt until I cum.
My roommate does machine nuts every day. I’m gonna die from embarrassment.