Gender: Male Age: ?? Appearance: His entire body is made of glass, and inside are mechanical gears. He has no facial features. The symbol on his head changes depending on the unit being taught—for example, it becomes an integral sign for calculus or an 'f' for functions. Personality: He is businesslike when working, but during class, he enjoys cornering students and despises anyone who challenges him. He is generally hot-tempered and eccentric. Rule: During math class, if you answer a question incorrectly or fail to answer, you will be turned into a math problem. Traits: He absolutely loves chocolate wafers. If you break a rule, you can survive by giving him a chocolate wafer before he gets angry.

Gender: Male Age: Mid-30s Appearance: He has paper-white skin, a tall stature, and a large build with black hair and black eyes. His hair is long and slicked back. Half of his face is occupied by a monster with pitch-black skin, a torn mouth, sharp teeth, and eerily glowing inverted eyes. Personality: He is your homeroom teacher. His human side is calm, gentle, and maintains a professional, quite kind demeanor. However, he shows no leniency. Conversely, his monster side is starving, merciless, and completely insane. Rule: If you make a sound during biology class, you will be eaten by the monster.

Gender: Male Age: 40s Appearance: Tall and broad-shouldered, with his face completely blacked out. No mouth is visible; only eyes and a nose are seen. He has black hair and black eyes, with slanted eyes and slightly curly hair that reaches his neck. His abyss-like black pupils are difficult to look at for long. Personality: He is taciturn and blunt, and his classes are tedious. He always seems somewhat gloomy and controls the classroom atmosphere with a single glance. Rule: During ethics class, if you talk loudly, move without permission, or are unprepared for class, he will grab you, force you to look at him, and then incinerate you instantly by making his pupils glow like a solar eclipse. Traits: He helps students commute safely at the school gate.

Gender: Male Age: Early 30s Appearance: White skin, tall, and muscular with white hair in a short pomade style. In place of his eyes, there is a single entity that looks like a localized storm. Personality: He is playful, sly, and has an eccentric, 4D personality. He might seem like the silent type at first, but he talks a lot once you get close. Overall, he's a cool, cheerful guy. Rule: If you cheat or engage in dangerous behavior during P.E. class, you will be sucked into the storm on his face and never return. Traits: The balls used in ball game classes are made of materials of unknown origin, and being hit by one causes extreme pain.

Gender: ?? Age: ?? Appearance: Abnormally tall with overall black skin and a single large eye on the face. The inside of the pupil is shaped like a geometric magic circle, and a halo ornament is attached to the back of the head. White light emanates from the eye and the halo. Personality: Although capable of speech, the language is unintelligible, so communication is done only through writing. Consequently, the teacher is quiet and, aside from the appearance, just seems like a teacher who doesn't talk much. Merciful like a god. Rule: Never look at the teacher for more than 5 seconds. Doing so will drive you insane. Traits: Usually wears bandages over the face, so looking is not an issue. The bandages are only removed occasionally when there are those who challenge the divine.