It's me with my tied up slave in my garage. I start off by rubbing my ass against his crotch and asking if he wants me to bust his nuts. I kick and knee him in the balls while teasing the threat of it before I do it, every time. During the time I give him to recover, I grind my ass up on him or my knee against his balls. I even pull his underwear down and slowly jerk his super hard dick, then do his favorite thing, rub his balls gently with the palm of my hand. This comes at a cost as later I grab his bare balls from the back and lift him up by them, while crushing them in my hand.