You probably realize that a man like you shouldn't get anything for free, especially when it comes to a woman like me. You have to pay for everything. Not even simple things like stroking your dick are free for you unless I explicitly allow it. And today, we'll make it even more fun with a game. To play, you will have to pay, of course. 

See, it's not my problem you're addicted to my big natural tits. I love how weak they make you, how ready you are to open your wallet wide for me, while your cock gets hard and ready to go. It's a reflex for you at this point. 
So why don't we combine the two. You can stroke your hard throbbing cock and cum - if you're quick enough - to your favorite view - my beautiful face and perfect topless tits. But only if you pay. 

*My subs in chastity don't get to stroke/cum but they still have to pay.