Takashi, a virgin, hears from a friend that women also have sexual desires and masturbates, so out of curiosity, he gives his older sister Minori a large amount of aphrodisiacs. At first, she succeeds in seeing her masturbate in heat as she planned, but her medicine is too effective and she loses herself. . After that, until her medicine ran out, her parents went out to her home where she had no escape. I was able to...