Haruka Iseumi

Lean of build, Haruka favors an entirely black uniform topped with a military-style cap bearing an emblem, and he ties a bandana around his head. His dark hair sweeps across to one side of his face. Most striking is the starter cord jutting from his chest, a near-perfect copy of the one Pochita gives Denji, though it turns out to be nothing more than a cosmetic surgical implant.

On the surface Haruka comes across as gracious and proud, forever announcing himself with theatrical flair and treating both his student council presidency and his leadership of the Devil Hunter Club as matters of great weight. He slides naturally into a leadership role, directing those around him and steering their talents toward whatever the moment demands. That generosity has limits, however, and he can turn cutting toward anyone he deems worthless, as when he tears into Asa for smashing her phone while trying to help.

He is also willing to deceive, posing as the real Chainsaw Man to inflate his own standing, yet the bravado collapses the instant he is cornered in the aquarium, where he confesses the cord is a mere implant and dissolves into hysterics begging the true hero to rescue him. His genuine adoration of Chainsaw Man, rather than any scheme, is what leads him to become the Chainsaw Man Church's public face, unlike the calculated motives of Barem and Fami. The cult's plot involving the Fire Devil weighs on his conscience enough that he vows to cut ties with Fami, only for his devotion to the legend to pull him straight back into danger.

Haruka first crosses paths with Asa Mitaka when he recruits her into the Devil Hunter Club, and when Yoru takes over and demands to know Chainsaw Man's identity, he flashes the cord in his chest and is briefly taken at his word. The group is later swallowed by an endless aquarium warped by the Eternity Devil, where his claim unravels and he admits to being merely a superfan who owns every scrap of Chainsaw Man merchandise. After Asa shatters the trap and Yoru slays the devil, Haruka lingers nearby, puzzling over the true nature of her power.

His worship draws him into the Chainsaw Man Church, where Fami and a shadowy Barem cast him as the movement's face while she works as its brains. Humiliated on live television by design and later parading a counterfeit Chainsaw Man, he grows increasingly uneasy. When Public Safety raids the church, Haruka and the other leaders are seized and locked inside the Tokyo Devil Detention Center. Freed by Asa and Fami with the Guillotine Devil's help, he warns Fami to keep away from his group, whose families have been ruined by her schemes, yet agrees to press on once he learns they mean to rescue the captive Chainsaw Man.

Deeper in the facility he makes the shattering discovery that the severed head of his idol belongs to Denji, the very classmate he knew, leaving Asa stunned at the revelation that the two are one and the same. The group escapes with Denji and regroups, only for Barem to corner them and reveal Nayuta's whereabouts before serving her severed head as a sushi dish. The horror pushes Denji to rip Barem apart as Pochita reclaims his body. After the Aging Devil is finally brought down, Public Safety takes Haruka into custody together with Katana Man, Nobana, and Seigi.