Kaoru and her colleague Ichiro have a late-life marriage. Ichiro has an only son, Hanzo, who never leaves the house, and the real reason for the remarriage is to have Kaoru take care of Hanzo. As expected, Hanzo lives with Kaoru as if she were his biological mother. Until one day, Hanzo begins to beg Kaoru, "I want a brother." Learning that Kaoru is nearing menopause, Hanzo falls into intense anxiety and ultimately decides to take matters into his own hands, trying to get Kaoru pregnant...