To fulfill the desires of clients seeking sexual relations with family members, Kuriki Takeshi launches a new project. Receiving a request from a brother who wants to have sex with his sister, he devises an elaborate plan by getting the sister hired at GOS, creating the perfect opportunity. About two months after she joins the company, he takes her to a hotel under the pretense of a site inspection. At the private bathhouse, they engage in mixed bathing while wearing yukata-style robes. Back in the room, she changes into a swimsuit for a photo shoot, then begins gonzo-style training. Her wet genitals are licked, and her ecstasy is secretly recorded. With her eyes blindfolded, the brother—having watched everything—appears and penetrates her with his erect penis.