Reiko, a mother living in a defective house with her son Kenta, is troubled by a plumbing issue and decides to call a professional to fix it. However, they decide to live frugally with water until the repair day. But when Reiko starts taking baths with Kenta to save water, he gets an erection seeing his mother's naked body. Noticing her son's change, Reiko realizes that he is now a man…
