Ripped the back of Jacob’s boxers

Paul reached down and cupped Jacob’s ass with his hand (eliciting a surprised jump from the latter) as Paul dug his fingernails into the cloth of his boxers, tearing a large chunk out, leaving Jacob’s ass completely out on display.

“Good luck dude.” Paul whispered into Jacob’s ear, before giving Jacob’s plump but muscular ass a slap and running off.

What now?