Takenaka Hanbei presents a petite frame with a childlike appearance, often mistaken for youth despite her unspecified age. She possesses large hazel eyes and medium-length silver hair tied at both sides. Her attire consists of a small turquoise sleeveless yukata layered over a white sleeveless top fastened by a bright blue bow, complemented by poofy arm warmers, fingerless gloves, tabi socks, and waraji sandals.

Her personality merges profound timidity with exceptional strategic intellect. She exhibits intense shyness around strangers, initially pleading "please don't be mean to me" during encounters, yet displays decisive leadership and tactical mastery in warfare. Preferring minimal-casualty strategies to demoralize foes, she discards pacifism when those she cherishes—particularly Sagara Yoshiharu—face threats, unleashing fierce wrath. Frail health and awareness of a potentially short lifespan once convinced her existence held no significance, leaving her devoid of personal dreams. She instead adheres to a rigid moral code, later forging unwavering loyalty to Yoshiharu and adopting his protection and success as her life’s purpose.

Hanbei endured significant hardship: childhood bullying fostered isolation and timidity, and early parental death left her uncle, Takenaka Shigetora (called Ando), as her closest kin. Initially serving as strategist for Saitō Dōsan in Mino Province, she defected to the Oda clan after Saitō Yoshitatsu attacked his father. Her allegiance permanently shifted to Yoshiharu when he, alongside allies including Akechi Mitsuhide and Hachisuka Goemon, rescued her and cultivated genuine friendship.

Her abilities rank her among Japan’s foremost strategists, feared by peers like Niwa Nagahide and Akechi Mitsuhide. Often likened to the tactician Zhuge Liang, she deploys intricate strategies such as the Stone Sentinel Maze—a lethal onmyōdō trap utilizing the "Eight Gates," where missteps cause drowning or death. As a potent onmyōji, she commands shikigami including:
- Zenki: her primary spirit, a former onmyōji whose aura overwhelms weaker entities.
- Gōki: a wolf-shaped spirit acting as her fierce protector.
- Twelve Heavenly Guards: a collective featuring entities like the Azure Dragon, Genbu, and Phoenix.
She manipulates elemental forces, exemplified by summoning water pillars against fire arrows. To curb spiritual power misuse and advance technology, she sealed the Dragon Veins—her power source—critically weakening her body. This required potent artifacts for survival; a sacred wood artifact temporarily restored her health.

Key events highlight her loyalty and strategic influence. During the Invasion of Mino Arc, Yoshiharu and Azai Nagamasa recruited her at a retainer event. Her double, Zenki, initially met them until a prank exposed her identity; she later defected to Oda following Yoshiharu’s intervention. Sealing the Dragon Veins worsened her health, though acquiring sacred wood facilitated recovery at a hot spring with the Sagara Corps. Her bond with Yoshiharu solidified as she committed to safeguarding him and advancing his goals, viewing him as a moral guide.

Relationships define her motivations. Devotion to Yoshiharu stems from his kindness and shared ideals, reshaping her worldview. She respects Oda Nobuna’s leadership but operates primarily through Yoshiharu. Uncle Ando remains her rare emotional constant, while shikigami like Zenki serve as extensions of her will—though Zenki eventually departed after a final battle. Reserved yet capable of warmth, she reveals protective instincts toward allies.