Masaru and Minoru are left living alone in their apartment while their parents are away on an extended business trip. The older brother, troubled by the mess at home, feels relieved when a housekeeper, Ms. Koharu Ono, is sent over before he leaves for work. Meanwhile, the younger brother, a student, can't take his eyes off Ms. Ono as she diligently cleans, completely unaware of his gaze. Entranced by her mature, sensual figure, his quiet longing begins to stir deep emotions. The brothers' ordinary life starts shifting into something new and unpredictable.