Riko, a married woman with hidden big breasts, lives with her son because her husband is away on a business trip. Her son's friend sees her not as a "friend's mother" but as a "woman". He suddenly commits the cruel act of raping her. However, after not having sex for a long time, Riko is surprised to find herself feeling pleasure. She doesn't want to admit her body's reaction, but as her son's friends use her as a sexual outlet, she gradually loses her reason. With her body played with by young men, this married woman is torn between pleasure and guilt!