Chiharu is an ordinary high school girl who lives in a perverted family. Chiharu has always been forced to have sex with her father and brother as if it were the most natural thing in the world. However, as Chiharu begins to feel uneasy about this strange family custom, she gradually tries to distance herself from her family. Her father gives her a deep throat blowjob. Her brother forces her into a slutty, urine drinking play. Her mother also has sex with her brother, resulting in a family orgy. This is the story of a strange family for whom incest is not considered abnormal, but normal.