I bet you're leaking pre-cum by now. I'd love to see you lick it up, why don't you take some on your finger and lick it. Stroke at a nice medium pace and get about 5 drops of pre-cum to lick them up each time.
Every time you leak pre cum from now on you have to lick it up. Even after we're done and you're with another mistress.
Keep stroking at a nice medium pace while you massage your balls with your other hand. Stroke yourself to the edge like this before we continue.