Michiru, a daughter-in-law, devotedly takes care of her father-in-law, Ryozo, even though she feels lonely after her husband goes missing. Not only that, but because of her husband's debt, she was run over by Sagawa, a yakuza-like man, and her feminine body reacted contrary to her hurt heart, and she desperately tried to suppress the voices that leaked out so that her father-in-law wouldn't hear them. Furthermore, her attractive body is eroded by her father-in-law's friend Sugiura... When Ryozo found out about this, he cursed Michiru for allowing his body to another man, and began subjecting her to lewd discipline.