Just be clear to him (tell him) you have changed your mind and you really want sex with him now. Or else he will hesitate and be confused. Also in your text, tell him if he doesn't have intercourse, you will suck him until his eyes sink into his head. There. That'll show him. (Guys like graphic explanations.)
And use a double-folded towel on the bed. Trust me. You don't want stuff leaking through sheets on to the mattress itself. And for pete's sake, light a candle for any odors.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
(Please note, we give the best advice we can based on the information given in a post. For better advice, please include the age of all romantic partners.)