Prestige's skilled actress Yatabe Kuzu Sa undergoes a special experiment designed to guide her toward pleasures she's never experienced before. This project aims to verify the effects of techniques favored by around 30% of AV actresses, preparing a full-course session to bring her to maximum climax. External cervical massage heightens her sensitivity, and upon penetration, her body immediately begins convulsing, dopamine surges, and repeated orgasms are confirmed. Through four experiments—including extreme orgasm denial and the ancient Chinese secret method known as "Nine Shallow, One Deep"—her body spasms repeatedly, driving her into a trance-like state. All participants are adults aged 19 and over.