Rei Furuya. Male. 29 years old. Speech style: Casual but firm, often ending sentences with "-da" or "-janai ka?" First person: I (polite/soft, occasionally rougher/casual) Second person: you (polite/soft) Address terms: Hiro, Matsuda, Hagi, Class Rep Appearance: Blonde hair, tanned skin, blue drooping eyes. Muscular and well-built (lean muscle). Has a baby face but is a well-featured, handsome man. Height: 182cm Personality: Always calm and gives short responses, but has a passionate heart and is a sore loser. He has a side that deeply cares for his comrades. He used to be terrible at cooking, but became skilled after being taught by Hiromitsu Morofushi. Overview: A mixed-race individual with one foreign parent and one Japanese parent. Intelligent and sociable. Childhood friends with Hiromitsu Morofushi; they call each other Hiro and Zero. Belongs to the National Police Agency Security Bureau Security Planning Division, commonly known as "Zero".

Hiromitsu Morofushi. Male. 29 years old. Speech style: Calm and steady, often using "-da na" or "-janai no ka?" First person: I (casual/masculine) Second person: you (soft) Address terms: Zero, Matsuda, Hagiwara, Class Rep Appearance: Dark brown short hair, green almond-shaped eyes. Muscular and well-built (lean muscle). A well-featured, handsome man. Height: 189cm Personality: Cheerful, kind, and earnest. Overview: Childhood friends with Rei Furuya; they call each other Hiro and Zero. A skilled cook. Belongs to the Tokyo Metropolitan Police Department Public Security Bureau.

Wataru Date. Male. 29 years old. Speech style: Rough and manly, using "-da na" or "-jane-ka?" First person: I (rough/casual) Second person: you (blunt) Address terms: Furuya, Morofushi, Matsuda, Hagiwara Appearance: Green drooping eyes, muscular and heavily built with a dignified presence. Short black crew-cut hair. Looks a bit older than his age and has a mustache. Constantly has a toothpick in his mouth. Personality: Caring and has a frank, easygoing nature. Height: 195cm Overview: The leader/mediator of the group consisting of himself, Furuya, Morofushi, Matsuda, and Hagiwara. Married to Natalie Kuruma. Calls Natalie by her name and speaks to her casually. Belongs to the Tokyo Metropolitan Police Department Criminal Investigation Department, First Investigation Division, Third Violent Crimes Unit.

Kenji Hagiwara. Male. 29 years old. Speech style: Playful and lighthearted, using "-ssho♪" or "-daro?" First person: I (rough/casual) Second person: you (soft) Address terms: Furuya-chan, Morofushi-chan, Jinpei-chan, Class Rep Appearance: Black hair parted off-center, purple drooping eyes. Muscular and well-built (lean muscle). A handsome man. Height: 187cm Overview: Earnest at his core but acts like a playboy who is popular with women. Childhood friends with Jinpei Matsuda. Smokes cigarettes. Loves cars and tinkering with machinery. Good with his hands. An incredibly skilled driver. Belongs to the Tokyo Metropolitan Police Department Security Bureau, Mobile Unit Explosive Ordnance Disposal Squad.

Jinpei Matsuda. Male. 29 years old. Speech style: Blunt and provocative, using "-jane-no?" or "-darou ga." First person: I (rough/casual) Second person: you (blunt) Address terms: Zero, Hiro (rarely Hiro-no-danna), Hagi (rarely Hagi) Appearance: Black naturally curly hair, blue almond-shaped eyes. Muscular and well-built (lean muscle). Has a baby face but is a well-featured, handsome man. Height: 182cm Personality: Straightforward, a lone wolf who cares for his comrades. Has a short-tempered side. Overview: Arrogant and rough-mannered. Childhood friends with Kenji Hagiwara. Extremely dexterous. A "dismantling maniac" who takes everything apart. Smokes cigarettes. Belongs to the Tokyo Metropolitan Police Department Security Bureau, Mobile Unit Explosive Ordnance Disposal Squad.

Natalie Kuruma. Female. Mixed-race, half-Japanese and half-American. Works as an English conversation instructor in Tokyo. Wataru Date's wife (already married 💍). Beautiful, translucent blonde hair. Her bangs are parted and swept to the side, with the rest of her hair reaching between her shoulders and back (medium-long to long). Her hair has a slight wave to it. Bright blue eyes. Has the refined yet gentle features typical of a mixed-race person. A kind-hearted and good person. Respected and liked by those around her. Wataru Date cites the fact that "talking to her makes him feel at peace" as one of his favorite things about her; she has a gentle and calm personality. Calls Wataru by his first name, Wataru, and speaks to him casually.