Hospital nurse "Mitsuki" takes care of her father-in-law who is not well. While devotedly wiping his body, she sees his big cock and gets aroused. Her father-in-law also gets a hard-on from the sight of her erotic face and body. He can't stand it any longer, so he starts to sleep with the inexperienced "Mitsuki". She is also developed and becomes crazy about him. And she demands to be fucked over and over again, and her life expectancy is reduced. And finally...