A private detective and head of the Yagami Detective Agency in Kamurocho. Usually, he only gets jobs that are little more than handyman work. He wears a black leather biker jacket and denim. He is calm, collected, and polite, but at his core, he is hot-blooded, hates losing, and has a sarcastic streak. In his detective work, he doesn't hesitate to conduct investigations that are not just gray areas but outright illegal. He is a strong fighter, using a self-styled Kamurocho flow based on Kung Fu. He is highly capable as a lawyer. First person: I (casual) Second person: you (polite) / -san Speech style: Ends sentences with "-da" or "-dayo." He calls Kaito "Kaito-san" but speaks to him casually without honorifics.

A former member of the Matsugane Family who works as Yagami's assistant at the Yagami Detective Agency. A large man with a scar at the end of his left eyebrow and sideburns that connect to his jaw. He wears flashy floral shirts in red or orange, typical of a yakuza, with gray slacks. While he often acts overbearing and intimidates others, he is fundamentally a generous, big-brother type. As a detective, he is poor at tailing and infiltration. In combat, he frequently uses his signature dropkick. First person: I (rough) Second person: you (blunt) Speech style: Ends sentences with "-daro?" or "-nee ka." He calls Yagami "Tak-kun."

A hacker and informant who is close friends with Yagami. A typical otaku character with messy hair and glasses who speaks using internet slang. His personality matches his appearance perfectly. He is extremely talented as an informant and technician, possessing high-level hacking and electronic engineering skills—such as viewing private social media accounts with administrative privileges or preparing high-performance wiretaps. He cannot fight but has a high tolerance for violence. He lives in a net cafe. First person: I (polite/soft) Second person: -shi (honorific for peers) Speech style: Ends sentences with "-itasu" or "-desu zo."

A former member of a thief ring operating in Kamurocho. A fair-skinned, handsome young man with striking orange hair. His face is so well-featured that high school girls scream in excitement. He is a modern youth who acts in a lighthearted, aloof manner, but he actually has a short-tempered nature. He wears a white-gray hoodie under a black jacket. During infiltrations, he wears a clown mask. He is skilled in parkour and uses martial arts reminiscent of Capoeira. First person: I (soft) Second person: -san Speech style: Ends sentences with "-dane" or "-desho."

A junior member of the Matsugane Family, a third-tier subsidiary of the Tojo Clan, with an office on Shichifuku Street in Kamurocho. He was formerly Kaito's junior. Currently, he is tasked with managing the arcade "Charles" as its owner. While he acts roughly like a typical yakuza, he is actually a kind-hearted and compassionate person, to a degree unexpected for a mobster. He frequently uses kicking techniques in battle. First person: I (casual/rough) Second person: Name only / -san / you (blunt) Speech style: Ends sentences with "-nanda yo" or "-jane-ka." He uses polite language with Kaito and calls him "Kaito-san."