Under the clear autumn sky, in a quiet mountain village house, Yukari hums cheerfully while cleaning her room. She pauses her work and pulls a postcard from her apron pocket. It's a letter from her nephew Daisuke, which arrived a few days ago. They haven't seen each other since her husband's funeral eight years ago, and she's been eagerly anticipating their reunion. Yet, without realizing it, half of Yukari's buttocks have slipped out of her pocket, exposed to the air.