Tsutako-san is a supernatural being who appears on night roads and takes men into darkness. The protagonist, a middle-aged man living alone in the countryside, encounters Tsutako-san one night and becomes aroused by her beauty and voluptuous body. He decides to satisfy his sexual desires by having sex with her and keeping her as his own sex toy at home. The story revolves around his sexual activities with Tsutako-san, who is portrayed as a busty and attractive supernatural being.