Whiplash 4: The Whip-Shock Experiment (1998)

A clinic's sexy nurse becomes the focus of a cruel experiment. Strapped to an exam table, she given a new kind of electro checmical shock treatment which has her arching in sweat covered agony and ecstasy. She is then given a sound whipping by a sadistic doctor, her reactions to pain and pleasure being noted as she cums hard under the lash. Meanwhile, two hot step sisters are tested and trained in a back room including a being flogged and pleasured with a vacuum device.