Hyōgo Asai sports a dark brown bob haircut framing pale skin and slate-blue eyes. Her initial attire—a sky-blue military jacket with white accents, yellow suspenders, and a silver-buckled blue belt—conceals her figure through layered bandages, paired with white gloves, heeled boots, and dual katanas sheathed on her left hip. Otomi’s kimono later reveals her physique, including a bust larger than Kiriko’s, contrasting her typically restrained appearance.

Blending respectful candor with impulsive judgments, she hastily accuses Keiichiro Tokugawa of her father’s murder, later offering earnest apologies and humility upon realizing her error. Solemn and disciplined, her sharp intellect and directness mask a vengeance-driven resolve, tempered by logistical struggles like evading capture and navigating borders.

Six months before the main narrative, her father’s unsolved murder ignites her quest for retribution, mistakenly targeting bearers of the Tokugawa seal. Hunger-induced collapse and Otomi’s subsequent aid underscore her vulnerability amid relentless pursuit.

Her alliances shift dynamically: recognizing Keiichiro’s empathy and paternal echoes, she collaborates with him, while gratitude toward Otomi secures her temporary bathhouse employment. Mutual respect defines ties with Chiharu and Kiriko, marked by candid discussions on virginity and physical contrasts. Antagonisms flare against Souji Okita and Houkouin, whom she dubs "Shigeyoshi’s woman" during clashes.

A agile swordswoman wielding dual katanas, she engages Keiichiro and Souji in skilled combat but falters against Houkouin’s brute strength and tactical dominance, acknowledging her limits.

Adapting to bathhouse life, she balances vengeance with teamwork, reflecting on her father’s memory while observing Keiichiro’s rapport with children—moments highlighting her emotional evolution and integration into a newfound community.