Ass Shaking on LetMeJizz
Unlike a choreographed twerk routine, this stays loose and unrehearsed, a woman bouncing and rolling her cheeks against a cock or in a lap with none of the dance-floor polish. The point is the jiggle itself, flesh set moving and caught close before things go further.
325 ass shaking videos here, all HD and all free. New ones go up daily, so check back if you don't find your scene first time around.