Nice to meet you, I'm your wife's younger sister—I'll be moving in from now on, she says as she arrives at our home. Her presence triggers a change in her brother-in-law's heart. One day, he catches her spending intimate time alone with her boyfriend. The shock awakens something uncontrollable within him. Drawn helplessly to his sister-in-law's figure, he falls into a daily routine of masturbation. Her very existence gradually takes hold of his mind. Daydream-like fantasies begin to consume his everyday life.