tup

The sound that comes from your belly button when you tap it at a certain angle.

"Damn it, she's tupping again!"
"How do you tup so loud?"
"Can I tup you?"

tup

The sound that comes from your belly button when you tap it at a certain angle.

"Nice tupping, man!"
"How can you tup so loud?"
"Don't make me tup you."