Ai is a housewife who wants a child. On her ovulation day, when the probability of pregnancy begins to rise, she receives a letter: "Congratulations on your pregnancy." Suddenly, a masked man appears, pins Ai down, and thrusts his erect penis deep into her vagina, filling her with semen. Unbeknownst to her, Ai's entire life had been watched through surveillance cameras. Without even realizing it, her body begins to react to the repeated ejaculations of the rapist. Eventually, the housewife carries a child in her womb from a man she doesn't even know...