"Hey, why don't you try and hold off on having sex? If you do that, your sperm will become thicker and you might be able to have a baby." Toshio and Aya are a married couple who have been unable to conceive. At Aya's suggestion, they decided to abstain from sex for a month. However, Toshio is forbidden not only from sex but also from masturbating, and after a week he becomes aroused and gets a rock hard erection. "Can he hold off?" Toshio worries, but what he should really be worried about is Aya's mother, Yumi, who lives with him.