To fulfill the wish of a client who wants to have sex with a relative, Hiroshi Takahashi steps up... The entire incest plan is secretly filmed! A consultation request from the brother of a mother who accepted the act with her son a year ago due to the plot of Director Karaki (Documentary Incest [53]). When the brother discovers a DVD that serves as decisive evidence of his sister's incestuous behavior, he asks Director Takahashi to find out the details. Posing as someone else, he contacts the mother and films her being fucked as part of the couple's hobby of being cuckolded. "If you do that, I'll cum!" she screams in ecstasy. A week later, they meet in secret without the husband knowing. She rides him cowgirl style with a blindfold on, unaware that her first threesome partner is her brother. Even after finding out, she continues, wanting to do it as her brother, moaning in pleasure.