Karakuni no Hirotari serves as a principal antagonist in the Utsunomiko anime, functioning as a powerful renegade Oni and a henchman to the sinister imperial leader Fujiwara no Fuhito. His role is defined by his opposition to the protagonist, Utsu no Miko, standing against the divine being and his companions who fight on behalf of common people.

As an Oni, Hirotari is a trained warrior, but his distinguishing characteristic is his possession of notable psychic or wizardly abilities, which set him apart as a formidable magical adversary. He uses these extraordinary powers in service of the Imperial government's oppressive campaign to consolidate control over the countryside through violence and intimidation.

Hirotari's personality is defined by his alignment with corrupt authority. He is a willing instrument of the state's repression, acting as a key agent in enforcing the will of Fujiwara no Fuhito. The narrative frames him as a corrupting and violent force, directly opposed to the heroes who use their own supernatural abilities for the protection of ordinary people. His motivations stem from this allegiance to the imperial power structure, as he actively works to crush resistance and subjugate the population.

Throughout the story, his key relationship is with his master, Fujiwara no Fuhito, whom he serves as a direct subordinate and enforcer. His primary conflict is with Utsu no Miko and the group of Oni warriors, including Tsuri, Takara, Kusuri, and Kagami, who train on Mount Kongo. As a renegade from the ideals that the other Oni uphold, Hirotari represents a perversion of their warrior class, using his skills for tyranny rather than justice.