So some of you did a great job at guessing what was going on here, even on your very first guess! Now you get to see it in action with the full size pics, and a few animated GIFs too. As always, don't forget to click on the pics to view them at their full size, and to see the GIFs animate.
So how did this go? Well, it was a few years ago, but if I recall correctly, it went something like this...
Me: I'm putting you in virtual chastity, boy. That means no jerking off, no rubbing your dick against anything to get yourself off, and you aren't allowed to even touch it other than a brief 15 seconds at a time when you pee and in the shower to clean...but not enough time to jerk yourself off to completion.
Boy: Yes Sir.
[the next day]
Boy: Can I cum today Sir?
[the next day]
Boy: Can I please cum today Sir?
Me: Nope! But since you seem to want to get yourself even more horny, I'd really like to watch a porn video tonight of a boy who is locked in chastity, tied spreadeagle on a bed, then released from chastity and slowly edged while he's tied up. How about you find one of those for me, boy? And I like longer videos, so make sure it's at least 15 minutes long.
Boy: Yes Siiiirrr.
[a few days later]
Boy: Um, Sir? Can I pleeeeeeeeeeeeeeeeze cum today Sir?
Me: Hmm, I'll think about it.
Boy: Pleeeeeeeeeeeeeeeeeeeeeeeeze Siiirrr?
Me: Boy, you sure are doing a lot of whining lately about wanting to cum.
Boy: Sorrrrry Sir.
Me: I think I'm going to give you an opportunity to cum today, boy.
Boy (surprised he's being given an opportunity to cum, and not being punished for whining): Really Sir?
Me: Yep. But you're going to have to do something to earn it. I want you to go get some finger paints, so they're safe for what I have in mind. Two colors, you choose the colors. And make sure you have a stack of letter sized paper available, around 30 or more pages should do it.
He didn't keep me waiting long, and obediently obtained what he needed for the task he was about to perform.
Me: Ok boy, show me everything you have. Good boy. Now since you've been whining about wanting to cum so bad lately, you're going to ask me very nicely if you can cum.
Boy: Please Sir, may I cum?
Me: Oh no boy, that's not exactly what I had in mind. You're going to write it.
Boy: With the finger paints, Sir?
Me: Yep, but you won't be using your fingers. At all. You're going to use that dick that wants to cum so bad. You'll write "Please Sir, may I cum?" One letter per page. Alternating colors for each letter. And your hands will NOT touch that dick the entire time. I want a full video of you doing this, from start to finish, so I can make sure your super horny self didn't cheat and touch that dick. Hold each page up to the camera after you finish it. Then when you're done, I want you to lay them all out in order and take a pic for me. Got it boy?
Boy: Yes Siiirrr.
So as you can see, like a good boy, he obediently performed his task exactly as I told him to, following all of my rules. And yes, I did allow him to cum after. (Come on, I'm not THAT sadistic to make him go through all of that, then take it back and deny him. Am I?) *grin*