Kimanjiro Inugane, nicknamed "Mad Dog," leads the Inugane Yakuza Group with strict authority. After subordinates Kentaro Yamamoto, Ryo Tachibana, and Kazuhiko Sugihara fail during a rival clan confrontation, he presents them with an ultimatum: commit ritual suicide (seppuku) with organ harvesting or undergo gender reassignment surgery in Thailand to become the female idol group, the Gokudols. They choose the latter, and Inugane oversees their transformation and rigorous idol training, acting as their producer, manager, and ultimate authority.

He maintains direct control over the Gokudols' careers, frequently issuing commands and imposing punishments for failures. His methods include physical intimidation, such as firing near their feet to induce adrenaline during critical situations. Despite his harshness, he takes pride in their dual identities as effective yakuza and successful idols, particularly after witnessing their combat skills and dedication during a hostage rescue targeting antagonist Seiji Koizumi. Inugane intervenes decisively, rescuing Koizumi's hostages and incapacitating Koizumi with a fireworks rocket launcher. He subsequently forces Koizumi to undergo the same gender reassignment surgery and idol training in Thailand as the original trio.

Subtle hints suggest complex ties to the yakuza world, occasionally depicted through solitary drinking scenes. He balances ruthless leadership with moments of mentorship, displaying a protective, almost fraternal concern for Airi (formerly Kentaro). His personality reflects practicality, organizational focus, rigid adherence to hierarchy, and a protective instinct toward his inner circle. He consistently prioritizes the financial and reputational interests of his yakuza operations, leveraging the Gokudols' popularity for profit and influence.