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Grab two buttplugs, one which he enjoys, one which he dislikes... (not to much, but a bit bigger...)
Tell him he has 3 minutes to make you orgasm, if he wants to choose his buttplug...
Time him, if he doesn't make it, then you have to wait for your orgasm as well...
Insert the selected plug. Tie him to the bed. Arms and legs to bedpost, spread eagle.
Tell him: " I want to use your dick for my pleasure now, you are not allowed to cum. If you get close, you are to alert me. I will stop. There will be punishment for not enduring.
If you at any point cum in me, whatever the reason, I will sit on your face until you have swallowed all your load."