To fulfill a client's request for a sexual relationship with a close relative, Kuriki Takeshi devises a plan. Responding to a brother's request to experience intimacy with his underground idol sister, he arranges for her to receive a beauty-focused massage, which she accepts without suspicion. Her highly sensitive reactions—twitching and melting with pleasure despite initial surprise at the suggestive massage—are vividly captured. Unable to endure the internal stimulation, she repeatedly arches her hips and climaxes intensely. With her vision blocked by an eye mask, she unknowingly permits penetration from her brother, who is disguised as an assistant. Moaning continuously about how good it feels, she panics when the mask is removed and realizes her partner is her own brother. Despite her distress, she is persuaded to continue and is thrust into further ecstasy. She then proceeds to suck the staff member's penis, escalating into a threesome. Writhing in pleasure from two penetrating cocks, she screams wildly, climaxing uncontrollably.