Tsukasa, who enjoys collecting underwear, would often wear her collection and indulge in fantasies in front of the mirror. However, her favorite sexy underwear was stolen. Suspecting her younger brother, Tsukasa quietly peeks into his room from the balcony. She finds him using her underwear to masturbate. The next day, she searches his room but doesn't find anything. Reluctantly, she decides to seduce him in her underwear to make him confess. Although her brother didn't easily admit it, he eventually confessed under erotic torture. From that day on, Tsukasa began to enjoy the sensation of dominating and erotically torturing her younger brother.
