Akira Kato - Doreizuma AKA Slave Wife (1976)

Synopsis:

When a stuck-up and privileged lady of a wealthy family is left to fend for herself, her butler decides to teach her some overdue humility through BDSM. His spiral of debauchery is soon overtaken by madness, and his sex games threaten to harm more than just her social standing and pride... Perhaps the most sadistic and bizarre film in Nikkatsu's lengthy Oniroku Dan/Naomi Tani collaboration, SLAVE WIFE (aka Captured for Sex 3) is a disturbing portrait of a man who’s life as a servant has driven him to revenge and ultimate satisfaction, and the beautiful woman who must endure his perverted wrath. Be warned, the final act is NOT for those who don’t realize how nasty Nikkatsu’s Roman Porno line can get.