Estim feels so fucking good, I don't get around to just beating off as much as I should. My balls are tied tightly and handing low. I beat them awhile then I grip my stiff dick and slap it hard. Precum is starting to leak, and I can feel the burn. I have to use lube to keep going longer, or I'll cum way too soon. Stroking my dick, my balls bounce and twitch between my fist and the chair. Finally it's too much, and I cum hard. For good measure, I twist my nipples to make my cock twitch a couple more times.