While the son is away on a three-day business trip, the father-in-law seizes the chance to pursue his daughter-in-law, a voluptuous beauty who has long caught his eye. He devises a plan, sneaking into her room and feigning a slipped disc to request a massage, then persistently groping her body. At night, he advances further, asking her to wash his back in the bath. Ultimately, over the course of three days, the daughter-in-law succumbs to pleasure from the father-in-law's insatiable cock in a creampie-filled affair.