Student council president Sayaka Shirotori secretly leads a double life as Fontaine, a vigilante hero known throughout the town. Always upholding justice, she takes bold actions against wrongdoing. One day, Suzuki Mitsuharu, a member of the Leg Fetish Club, begins stalking her and secretly films her without consent. Sayaka issues a stern warning, but Suzuki ignores it, his obsession with her legs only intensifying. Determined to uncover her secret identity as Fontaine, Suzuki orchestrates a crime of his own. He lures Fontaine into a trap, exploits her vulnerability, and forces her into a bizarre demand—punishing them using only her legs. Ultimately, Sayaka faces an unexpected and devastating BAD END.