Minami is entrusted with caring for the elderly Yamada to pay off her father-in-law Tokuji's debt, but Yamada forces Minami to not only care for Minami, but also to take care of his private parts. At first, Minami is Minami by this unexpected turn of events, but she gradually realizes that she feels abnormally excited by having sex with the elderly man, and eventually she begins to desire her father-in-law Tokuji's body...