Ball Fold-Over
A ball fold over is where the base of your penis meets your scrotum. You can't see the ball fold-over because hidden by the cock.
"I totally got some lint on my ball fold-over the other day"
"I like it when she performs oral sex on my ball fold-over"
"mmmmm mmmm....mmmmMMMMMM"
"My ball fold-over is sore from gyrating"