Kuruma Tanaka is the deuteragonist, primarily known as Kuruma. He works as a spy for the Japan Safety and Promotion Company. Assigned as Botan Negoro's partner for the critical "Mission T," their objective is to recover dangerous crystalline fragments called the "Shards of Tesla" before they can be assembled and used catastrophically.

Kuruma possesses shaggy black hair, purple eyes, fair skin, and a medium build. His personality is arrogant, complaining, loud, and confrontational. He frequently talks down to others, especially Botan, displaying chauvinistic attitudes. He neglects basic spy protocols, like maintaining cover, and exhibits entitled behavior, such as demanding access to restricted areas disruptively. His professionalism often falls short compared to Botan's discipline.

Despite his flaws, Kuruma develops through his partnership with Botan. Initially dismissive and uncooperative, he gradually gains respect for her abilities after witnessing her competence during missions like their operation in Oslo. He becomes protective of her, signaling a shift from their adversarial start. His role evolves into one of mutual reliance, though their interactions remain contentious.

Kuruma's specific spy skills are not extensively detailed. His primary narrative function centers on his partnership with Botan and their joint efforts to secure the Tesla fragments against rival organizations. His background, upbringing, and life beyond Mission T remain undisclosed. His development is confined to his professional relationship with Botan and adapting to the mission's demands.