Carnal Revenge (1974)

A businessman cheats a count out of his seaside castle. He moves his sickly wife to the castle and while she's terminally ill and bed-ridden, he proceeds to freely philander with his wife's nurse, who actually falls in love with the cad, with his sexy blonde secretary, and with a young college girl, who is part of group students hanging around the beach whom he takes sailing on his yacht while his ailing wife and love-struck mistress are stuck at home. He gets his comeuppance though when one of the women he has wronged basically decides to screw him to death. She is the daughter of the old evicted count.