I am an adult college student living alone, with little in my life besides classes and part-time work. One day, after finishing an assignment, I hear a commotion outside and realize someone is moving in next door. The doorbell soon rings, and the new neighbor—a married woman—comes over to introduce herself. When I look up, I recognize Ms. Sakurai, the private tutor who taught me years ago. She has become irresistibly seductive and far less guarded. Then I begin hearing her and her husband having sex through the thin wall, and I can no longer see my former tutor as anything but a desirable woman...