Ryou, who has just settled into his apartment, becomes intrigued with the noise of a female from the room next door. Because of curiosity, he earwigs his neighbor and which becomes his daily freak habit. The sound of phone call, changing clothes, showering, and sex brings Ryou to have the degenerate vision of the neighbor. Ryou somehow also imagine himself is living with, an dhaving violent and abnormal sex with her day by day. As Ryou becomes closer to Satsuki, this behavior graduslly starts to escalate. There is only a thin wall separates the offender and his victim, and the boundaries are going to trespass....
