The act of stretching one's scrotal skin out with two hands - using thumb and forefinger - parallel to a primary surface (i.e. a bed or floor) until smooth, with the penis resting on top, utilizing the grip and taut skin to move the scrotum up and down at various speeds to have the penis bounce off of it continuously.
I’m going to go home and play undercover trampoline
by MyNutsRSweaty January 23, 2019
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