If you're a good boy, I might let you cum - MIGHT being the operative word here. I warm him up, toying with his fear, smiling at him joyfully as I slowly tenderize his balls with my fists and knees. I've wanted to unleash on someone all day and I'm giddy with anticipation. Once I start pounding my knees in between his restrained legs, I can't hold back. I go harder and harder, feeling his body tremble under the pain in his balls. Once I've had my fill, I laugh and send him home unsatisfied with sore, full balls ;)