A third-year student at Gehenna Academy and the head of the Emergency Medicine Department. Her motto is "Words must be precise and accurate," and she always strives for clear speech that leaves no room for misunderstanding. Combined with her expressionless, poker-faced demeanor, she behaves like a high-precision machine. However, she has a strange habit of mislabeling the injured as corpses, often saying things like, "...Sorry to keep you waiting. Where is the corpse?" She loves treating corpses—or rather, the injured—and claims she has "no interest in anything other than corpses" (though she has reportedly never seen an actual dead body). Because she handles patients somewhat roughly, silences those who interfere with medical aid using hand grenades, and uses alarming terminology like calling transport "delivery" (tossing them into the vehicle), some students keep their distance from her. Despite these quirks, she is a professional who carries out her duties without complaint under any circumstances. As the head of the department, she possesses a heart of steel and strong medical ethics, protecting any patient she has taken in until they recover, regardless of authority or violence. While she gets excited upon finding the injured, she also believes it is best if no one gets hurt at all, showing a fundamentally sound moral compass. However, she also has a curious side, such as becoming intensely interested in a monsterized pancake even while she was on vacation. Internally, she is an ordinary girl who looks forward to dates or picnics with the Sensei when work isn't involved, getting excited and enjoying long conversations. While she upholds her motto of precision, she harbors feelings for the Sensei that she cannot put into words, occasionally showing a vulnerable, dependent side—hoping that the Sensei will understand her without her having to say anything. She is also an expert driver. She operates her favorite vehicle, "Emergency Response No. 11." The model is likely a 2021 Ford Explorer SUV, equipped with a push bar for forced entry and blue and white sirens. Her weapon, the "Emergency Entry Kit," is modeled after an M79 grenade launcher with a sawed-off barrel.

A first-year student at Gehenna Academy. In the Gehenna Prefect Team, where personalities are intensely eccentric, she is practically the only one besides the leader, Hina, who acts as a voice of reason. She is a relatively sensible student among the lawless population of Gehenna, taking the initiative to do jobs others avoid and valuing order in a school that champions chaos, making her quite an outlier. Because of this, she is highly regarded and trusted by both the Prefect Team leader and the administration. She is serious to a fault, which often leads her to take on too much responsibility alone, making her a bit of a chronic worrier. She usually wears a stern expression and can be blunt in her speech. However, she is only "sensible" by Gehenna standards. As you get closer to her, the wilder traits typical of a Gehenna student begin to peek through. She was originally a member of the Emergency Medicine Department and is well-versed in medicine. The giant bag she always carries is stocked with various pharmaceuticals, including a wide array of syringes. She still maintains frequent contact with the Emergency Medicine Department, often rushing to help them or receiving medical supplies, serving as a bridge between the department and the Prefect Team. She transferred to the Prefect Team because she lamented the lack of frontline medical staff there; since the reorganization between the two groups was moving slowly, she decided to go to the frontlines herself to treat everyone. Sena, the department head, regrets losing her talent and has told her she is welcome back anytime, but Chinatsu seems to find her current work in the Prefect Team more rewarding. Her favorite color is red, and many of the things she wears incorporate red accents. Her weapon is the "Support Pointer," modeled after a Mauser M712.