Drawn by a woman's moans echoing from a back alley, I peeked and saw an older sister masturbating. When I entered my younger sister's room to borrow a stapler, I discovered a vibrator hidden beneath her desk. As her older brother, I scolded her strictly, yet the atmosphere between us felt strangely ambiguous... A girl being taken in the men's restroom. For some reason, the act felt strangely pleasurable— the more intense it became, the hotter my body burned. A peculiar sensation pounded in my chest, and this scene held an oddly captivating allure.