Des:Seigo and Miki, who had been married for two years, tried to conceive by abstaining from sex for a month and releasing stored sperm, which coincided with the fertile period before ovulation. Mikis sister Mina, who lives nearby, also wants a child but is unable to have sex due to her husbands ED and busy work schedule. Mina, who wanted to get pregnant before her sister, seduced Seigo by not wearing a bra and exposing her nipples on the day her sister and husband were due.