“Seeing as you're clearly a horny little slut, I’m gonna treat you like one. And what do horny little sluts like you do? They hump things that’s what! So I demand that you lie face down on this towel and hump away right now! Don’t worry, you won’t get a sandy cock. That’s what the towel’s for stupid. I want you to do that for 30 seconds, during which time your hands are NOT allowed to touch that cock at all! And remember - no touching, no stopping and no cumming!"
[After 30 seconds, you are allowed a 20 seconds rest]