Himeno

Himeno is the veteran of Division 4. Aki's old partner. The woman who shows up on Denji's second day already tired of this job. She wears an eye patch over her right eye because she gave that eye to the Ghost Devil years ago, and in exchange the devil wraps around her arm like a sleeve of black smoke and strangles things for her.

She is the warmest person on the team, which mostly means she is the one who drinks the most. She teases Denji, protects Kobeni, watches Aki in a way he has never once noticed, and at the bar after a hard job she tells him she is only into men who are missing a few screws. When Denji refuses to back down during the Eternity Devil fight and climbs into the monster's body to kill it from the inside, Himeno stares at him for a long moment and quietly falls in love with the wrong person.

Her death comes in episode 8. Katana Man and Akane Sawatari ambush Division 4 in a coordinated hit. Aki is about to be cut in half. Himeno burns her entire body as the cost of the Ghost Devil's full release, turns it into a monster big enough to match Katana Man for a few seconds, and disappears. Aki wakes up alive in the rubble with nothing left of her. She reappears once, four episodes later, as a voice inside the Ghost Devil that hands Aki a cigarette from the other side and tells him she is sorry she never said it.