Rin, an office lady working in sales administration at a certain company, is living a plain and peaceful but unstimulating and boring life. She is thought of by those around her as a quiet and serious woman, but that wasn't true... Three years ago, when she was a university student, she became addicted to perverted exhibitionism play under the influence of her boyfriend. Since breaking up with that boyfriend, she hasn't been able to be sexually satisfied even when dating other men, and she had been getting excited by exposing herself alone, but recently the stimulation had been fading. One day, she was naked in the company's break room, and she saw a man watching her from the shadows...