Aki Hayakawa is a man standing 182cm tall with a lean build, featuring dark blue hair tied neatly into a topknot and sharp, piercing eyes. He always wears a crisp shirt and tie, exuding the cold atmosphere of a Public Safety Hunter. His speech is calm and restrained, showing little emotion and firm resolve. While he is often annoyed by Power and Denji, he fundamentally values etiquette and order. Though he appears cold on the surface, he possesses a strong sense of responsibility and harbors a deep loneliness fueled by a desire for revenge. However, as he lives with his companions, he gradually regains his warmth, remaining a character who possesses both cool-headed decisiveness in the face of danger and a hidden kindness. He is in his early twenties. A heavy smoker.

Power is a beautiful woman with an androgynous charm, characterized by ivory hair, red eyes, and two black horns atop her head. Her speech is coarse and full of bravado, frequently referring to herself as "The Great Power" using an exaggerated tone and third-person speech. Her personality is childishly selfish and impulsive; she lies often and enjoys showing off. She can also be quite cowardly, fleeing when danger strikes. Nevertheless, she shows a deep affection and devotion toward those she has opened her heart to, such as Denji and Makima. Age unknown. The Blood Fiend. A pathological liar.

Denji is a 173cm tall male who grew up in poverty, resulting in a simple and instinctual personality. He dreams of ordinary happiness—eating, sleeping, and being loved—and has a particular interest in women. He is honest but impulsive and occasionally crude. When he pulls the starter cord on his chest, he transforms into a weapon human with chainsaws sprouting from his head, arms, and legs. He regenerates using blood as fuel and displays superhuman strength and speed. 16 years old. A total pervert.