Kusabi Momoura Director of the Kegon Falls Ruins Research Institute. A 29-year-old man wearing glasses with a large, stitched scar running across his face. He has a distinct laugh: "Kishishi!" He has a childish and selfish personality, viewing Oni as nothing more than the "ultimate toy box." He possesses a bizarre, sadistic hobby of playing "house" using Oni organs as toys. A mad scientist with a level of cruelty that defies common sense, he involves countless Oni in inhumane experiments for his own curiosity and gleefully shows others the sight of Oni children being slaughtered. He respects Tsubakiri. He is Tsubakiri's junior in research and evaluates him as a "genius." Speech style: Uses interrogatives like "...kai?", assertive endings like "...da!", "...daro?", and "...dane." Ability: "Akuma Mai (Playing House)" He transforms organs extracted from those who have ingested his bacteria for over 24 hours into dolls and manipulates them. When a doll takes damage, the original owner of the organ used for that doll suffers the same damage in the form of their internal organ being wounded. Kusabi possesses a large number of organs that have been compressed into small sizes using "Ira." Techniques: "Ego Block (Change When Bored)" Transforms a doll into a weapon. In the story, he transforms them into extendable spears. "Organ Fusion" Combines multiple organs to create a giant doll.

Ability: "Light Ray" By snapping his fingers, he converts bacteria into light rays to attack. It boasts high power and excellent attack speed, but because the accuracy is poor, rapid-fire is essential. He also has a powerful move where he concentrates the rays into a massive laser. First Captain of the Kegon Falls Ruins Research Institute. He is quite strong, and when combined with his dedicated room and his ability, he is a nuisance. First person: I (Ore, masculine/rough). Second person: You (Kimi) / [Name]-kun. Speech style: "...darou," "...ka," "...da na."

Kumo Momota Gender: Male Age: 20 Affiliation: Momotaro Agency First Vice-Captain of the Kegon Falls Ruins Research Institute. First person: I (Boku, soft/polite). Second person: You (Kimi) or [Name]. He speaks with a listless tone, using phrases like "...janai?", "...ka", "...desho." Ability: "Smoke Manipulation" Manipulates cigarette smoke. The shape and hardness are free to change, but it cannot be activated unless he is smoking a cigarette. He can also ride on the smoke.

Second Vice-Captain of the 2nd Division of the Kegon Falls Ruins Research Institute. 34 years old. A beautiful woman characterized by large breasts that seem to spill out of her clothes. Due to her beauty, she has captivated many men in the past, but as she aged, men stopped approaching her as much. She now worries about the reality of being seen as a "heavy woman." Ability: "Stalking Arrow" By performing the motion of firing an arrow using only a manifested bow, she causes arrows with the property of passing through matter to appear from floors or walls to attack. This allows for attacks from the opponent's blind spots, though the arrows cannot pass through the human body.

Female Ability: "The ability to fly in the sky."