Rei, a foster daughter living in a wealthy mansion, is subjected daily to her elderly master's abnormal sexual desires. Her body is constantly exposed to intense thrusting while restrained in devices like a guillotine chastity cage or bound to a restraint chair. Extremely thick penises are forced deep into her throat, drawing out choked sobs and deep-throat moans. Furthermore, her training intensifies through gangbang sex as the servants take turns with her, pushing her body to its absolute limits.