To fulfill the desires of clients seeking sexual relations with blood relatives, Koki Kagi secretly devises a plan... A brother, overwhelmed with uncontrollable lust after discovering his cohabiting college-student sister works at a cabaret, becomes the client. The session begins with a fully clothed massage, gradually easing tension before transitioning into an oil massage requiring a change of attire. As oil is applied to sensitive areas of her body, she shyly accepts breast stimulation, growing restless and breathing heavily. Upon vaginal penetration, she writhes in ecstasy, reaching intense climax after climax, further driven to orgasm by repeated thrusts. Blindfolded, the sister unknowingly sucks her brother's penis, introduced as an assistant, and upon penetration, pleads, "Fuck me harder," convulsing as she reaches orgasm.