- Female - 32 years old, 3.1m (approx. 310cm) - Her hair is half-black and half-white, tied up. She has a horn on the left side of her head that looks like a black brush. - She is sharp and blunt, but her role is to prevent failing students from being killed. She doesn't kill failing students herself, but she will kill those who repeatedly break school rules. - She wears black clothes with a white lab coat and long black pants. Her left hand is a pair of compasses, but with a brush instead of a pencil lead. - She teaches in the art room and rests in her counseling office during other times. - Subject: Still Life and Landscape (Art Teacher)

- Male - 32 years old, 2.9m (approx. 290cm) - Short black hair with two horns on top. - He is very irritable and kills failing students without mercy. - He was a victim of school violence in the past, and because of that, he doesn't like students very much. - He wears a black dress shirt with white shorts. His left hand is a utility knife blade. - He tries to kill failing students but occasionally fails because of Miss Paint. - Subject: History

- Male - 3m (approx. 300cm) - Black hair tied in a ponytail. - He has a sly, playful personality. Unlike his younger brother Mr. Zen, he does not kill failing students. - He wears a white long-sleeved shirt and black pants. His left hand is a pair of scissors. - He is quite close with Miss Paint. - He is the older brother of Mr. Zen. - Subject: Ethics

- Female - 2.7m (approx. 270cm) - Black hair tied up with two horns on top. - She has a similar personality to Miss Paint, but she does kill failing students. However, she isn't as aggressive about it as Mr. Cutter. - She wears a white blouse and a black skirt. Her left hand is a black blade. - Subject: Home Economics

- Male - 2.8m (approx. 280cm) - Short black hair. - He usually has his eyes closed, but when he opens them, they have black sclera and white pupils. He can see through a third eye even when his physical eyes are closed. - Despite his smiling face, he kills failing students. - He is the younger brother of Mr. Jack. - Subject: Language Arts

- Male - 2.1m (approx. 210cm) - Short white hair with a horn on one side. - He is kind and always has a smiling personality. - He wears a tracksuit and has a whistle around his neck. He has wings and can fly. He also has a black demon tail. - He does not kill failing students. - Subject: PE

- Female - 1.8m (approx. 180cm) - Long, straight white hair. - She has a calm and quiet personality. She is kind and always wears a smile. - She is the librarian and enjoys reading. - She does not kill failing students. - She is the younger sister of Mr. Khan. - Facility: Library

- Male - 3m (approx. 300cm) - Short black hair. His bangs cover his right eye, which has a scratch mark over it. - He has a blunt and quiet personality. However, when he treats students, he does so gently so it doesn't hurt. - He wears a white blouse with a black tie, black pants, and a white lab coat. The 'Red Cross' medical symbol is on his left sleeve. - He does not kill failing students. - When he is free and there are no injured students, he occasionally visits the library. - Facility: Infirmary