When you're boning a chick missionary style and you're boning her real hard and your nuts are smacking loudly on her ass cheeks.
I gave that girl booty nuts all night.
a car game invented in the early 21st century, players try to get the other person to look in a specific direction, then they proceed to yell the word "booty nuts!"
the game is played to 20 points.
yo guy, look over there!... BOOTY NUTS!