Get some precum on your fingers and rub it on your pussy or just rub your pussy on his cock to get some right from the source! Say "Let's get a little pre-cum on there for you to lick off!"
Then have him go down on you.
Moan and tell him how much it turns you on thinking about him being denied.
Tease him about how he could be slamming his cock into you, spurting his cum...
BUT instead he gets a ruined orgasm and a mouthfull of cum!
Have him give you an orgasm, after you are satisfied, make sure he is teased sufficiently! (Just don't push him over the edge yet!!)