Junsuke is surprised by the sudden visit of his mother's friend, Senri. As he struggles to suppress his feelings of distress amidst her mature allure, Senri, touched by Junsuke's unwavering affection, convinces herself it will be just a one-night affair and secretly engages in a relationship. The next day, despite urging Junsuke to stop when he begs for "one more time," she succumbs to the intensity of the young man. However, even brief trysts must eventually come to an end...