Otome Okunomiya, a retired Major from the Imperial Army's military police, now owns the café Kuronekotei. She took over after its previous owner, Nagi Tōma, left for an overseas technology exchange program; their professional relationship dates back to their time as co-workers during the war.

She possesses long blond hair, typically arranged in a braided bun with wavy shoulder-length strands framing her face, and reddish-pink eyes. Her attire maintains a formal military-inspired aesthetic: a white cape over a white uniform, gray nylon pantyhose, a black belt, and white high-heeled shoes.

Otome consistently displays an authoritative and calm demeanor, even under pressure. She adheres strictly to rules and regulations but demonstrates flexibility when circumstances permit leniency within legal boundaries. Her speech reflects her disciplined background through a formal and commanding tone.

A lesser-known aspect is her ability to play the piano, a skill she possesses yet feels self-conscious discussing openly. Her name reflects aspects of her character: "Otome" translates to "virgin" in Hiragana, while "Okunomiya" combines the characters for "inner part" (奥) and "temple/shrine" (宮).

As proprietor of Kuronekotei, she oversees operations where former military automata dolls work as waitstaff, maintaining order while facilitating their transition to civilian life.