Sadahiro Mibu, a contracted monk of the Kōgon Sect, serves as the partner to Shikabane Hime Akira Tōoka. Wielding the sect’s sole authorization to kill humans—a privilege born from his five-year exile prior to the series—his past remains shadowed by unresolved actions during his early training alongside Keisei Tagami and Akasha Shishidou, former comrades whose bond fractured into divergent paths.

Posing as Café Parthenon’s manager, he cultivates a deliberately laid-back persona, clad in casual wear with a cigarette often in hand. This façade masks his covert role monitoring Ouri Kagami and Keisei while aiding missions against rogue Shikabane. His combat prowess combines Zadan techniques—esoteric arts amplifying Akira’s long-range precision—and a dagger for close confrontations.

Volatile exchanges define his partnership with Akira, his reckless actions and irreverent quips frequently met with her physical retribution. Yet their alliance endures, unified by their mission to eliminate rogue Shikabane Hime. His pragmatism extends to former friend Akasha, whom he hunts without hesitation after the latter’s betrayal, prioritizing duty over fractured history.

Following Keisei’s death, Sadahiro assumes reluctant mentorship of Ouri, guiding him through the burdens of a contracted monk. Reinstated after exile, his allegiance to the sect remains complicated, balancing nonchalant charm with tactical rigor.

Sporting dark brown hair, a nose-spanning scar, and a consistently disheveled appearance, his ties to the Hoshimura legacy surface sporadically in interactions with Makina and Ouri, hinting at deeper connections to the Seven Stars conflict. Yet his focus stays fixed on immediate threats.

His narrative arc centers on operational demands over personal introspection, with conflicts against the Shichisei and Akasha cementing his role as a seasoned, morally ambiguous operative within the Kōgon hierarchy.