"I want to pass the university entrance exam this year..." Kenta, a student who lives alone in Tokyo and spends all his time studying, has one moment where Kokoro relax. That moment is when he interacts with Yumi, a married woman from the Yasuno family who lives next door. One day, Kenta visits Yumi's house on some business and encounters her doing the laundry in the garden. "There's something different about Yumi...?" That's when Kenta realizes something. The fact that Yumi is not wearing any underwear! From that day on, Kenta has not been able to forget the image of Yumi without any underwear...