When Mizuki Hijiri moved to a new school, she hoped for a typical school experience, yet fate had other plans when she encountered the renowned Hero Club. Each member, all boys, grapples with their own chuunibyou—Yamato Noda embodies a valiant hero, using his athleticism for noble causes; Kazuhiro Nakamura believes he's the hybrid offspring of a demon and an angel, named 'Touga Ryushouin'; Tomoki Takashima, a charming otaku fixated on the fictional character Sora; and Rei Tsukumo, the covert puppet master. Reluctantly pulled into the Hero Club fold, Hijiri finds normalcy elusive. Despite their eccentricities, genuine bonds form among them, promising a thrilling odyssey as Hijiri delves into their shared illusions of grandeur.