Mutsuki Asahina, a tomboyish and strong-willed member of the Holy Student Council, hails from a family of shrine proprietors, serving as a miko trained in exorcism. She wields a prayer stick with practiced precision, employing her signature "Asahina Special" technique to forcibly expel spirits from possessed individuals—a skill frequently directed at Kazumi Ryudo, whose susceptibility to possession makes him a recurring target.

Vibrant red hair and a curvy frame distinguish her appearance, while her personality blends fiery determination with aggressive shotacon tendencies. The latter drives a mischievous fixation on Nino, a childlike spirit bound to a statue, prompting playful harassment ranging from blackmail via compromising photos to persistent efforts to clothe him in shorts. Despite these antics, Mutsuki’s leadership often overshadows the council president’s, as she decisively takes command during crises.

Tasked by the school chairman with managing supernatural disturbances, she initially resisted the role but acclimated quicker than her peers. Her dynamic with fellow council members balances impish humor with pragmatic resolve, though her interactions with Nino and Kazumi regularly ignite comedic friction.

Adaptations uniformly emphasize her miko duties and shotacon proclivities. The anime highlights her humorous escapades in episodic formats, while the manga introduces expanded plot threads and exclusive characters. Neither medium deviates from her core identity, cementing her traits as unvarying pillars of her character.