Aya, a female doctor who is a surgeon at a private hospital in Tokyo. She is made a subject of a human experiment because she rejected Mori, a colleague doctor who seeks physical relationships only by sexual desire. What is the secret experiment conducted in the hospital? "The newly developed unlicensed drug has increased the sensitivity of Dr. Sakurai's Portio by hundreds of times." Aya who can't stop feeling the aching sensation in the back of the uterus ... The woman becomes captivated by the feeling of Portio.