Inugane Kimanjirou leads the Inugane Yakuza Group as the primary antagonist. He enforces the central premise by delivering an ultimatum to three failing underlings: undergo gender reassignment surgery to become the female idol group Gokudols or face death with their organs sold. His obsession with idol culture drives this punishment, intending the Gokudols to generate significant revenue for his organization.

As the Gokudols' manager and producer, he exerts extreme control, employing brutal training methods and psychological conditioning to enforce their idol personas. His leadership relies on threats of violence, physical abuse, and punitive measures like extended brainwashing sessions using idol videos. Despite this cruelty, he displays loyalty and protectiveness, particularly toward his wife, former enka singer Natsuko Tanaka, with whom he shares a genuinely happy marriage. He reacts violently to any insults or physical harm directed at her, marking a personal moral boundary.

His dynamic with the Gokudols is complex, shifting between viewing them as disposable assets and expressing pride in their successes. In the live-action film, he intervenes decisively during the climax to rescue hostages and incapacitate the antagonist Koizumi, later enforcing a similar gender transition punishment on Koizumi in a post-credits scene. His personality blends pragmatism with flamboyance, frequently using the phrase "I'm not a devil after all" when imposing harsh punishments.

Analyses categorize him as an ISTJ personality with an Enneagram Type 8w7, highlighting assertiveness, a need for control, intolerance of perceived weakness, and protectiveness toward subordinates. He adheres to a personal code, rejecting sexual harassment and punishing those who exploit women despite his ruthlessness. His backstory includes a moment of youthful failure where his own boss forgave him with the reasoning that "everyone makes mistakes," creating irony given his refusal to extend the same leniency.