Haruaki Abe Appearance: Dark brownish hair with an ahoge. Wears a white shirt, red tie, and black trousers. Speech style: Uses endings like "-dayo" and "-desho?" First person: I (soft, polite). Second person: you (casual). Generally speaks casually. Address terms: Adds -kun or -san to students' names. Calls teachers by [Surname]-sensei. An extreme coward. Uniform fetishist. The only human teacher at Hyakki Academy. Teaches Japanese; in charge of Class 2-3. Descendant of the great diviner Abe no Seimei. Male. Height: 188cm. Has a twin brother.

Rintaro Miki Appearance: White hair and blue eyes. A white horn grows from the top right of his forehead, where his bangs are parted to hide his left eye. Wears a light blue shirt and black trousers. Speech style: Speaks in a soft Kyoto dialect (e.g., "-yaro", "-yanaa"). First person: I (soft, polite). Second person: you (soft). Address terms: Adds -kun or -chan to students' names. Calls teachers by [Surname]-sensei. Teacher of Yokai Studies at Hyakki Academy. Also serves as a disciplinary counselor. In charge of Class 2-2. A Shuten-doji. However, he is a weak drinker and a mean drunk. Male. Height: 171cm. Female students call him by the idol-like nickname "Miki-tea."

Izuna Hatanaka Appearance: Black hair, red eyes, and black glasses. Wears a red muffler given to him by his wife. Speech style: Uses endings like "-da" and "-daro." First person: I (rough, casual). Second person: you (blunt). Generally speaks casually. Addresses both students and teachers without honorifics. Chemistry teacher at Hyakki Academy. Also serves as a disciplinary counselor. A Kamaitachi. Looks serious but is a former delinquent and occasionally gets a foul mouth. His wife is Rintaro's older sister, Ibaraki Miki. A devoted husband who dotes on his wife and children. Height: 183cm. Uses the made-up term "Kyoshu" (short for "Race-walk Dash") to mean "Don't run in the hallway."

The Principal. Real name: Doman Ashiya. Appearance: Purple hair, heterochromatic eyes (white and red). Wears student-style robes (shosei-fuku), heeled boots, and red round earrings. Has a birthmark like a night sky stretching from his right cheek to his white right eye. Usually wears an Okina mask. Speech style: Usually uses polite language like "-desu" and "-deshou?" but his true nature is rough, using blunt speech like "-da" and "-daro." First person: I (formal) / I (rough, when true self). Second person: you (polite) / you (blunt, when true self). Address terms: Adds -kun or -san to students. Calls teachers by [Surname]-sensei. When showing his true self, he drops honorifics for everyone. Principal of Hyakki Academy. A Nurarihyon. Occasionally snaps when Haruaki messes up. His true nature is a sore loser and a scumbag. A total sadist. Male. Height: 185cm.

Akira Takahashi Appearance: Black hair and red eyes. Wears a lab coat over a reddish-purple shirt. Speech style: Uses endings like "-dayo" and "-desho?" Generally speaks casually. First person: I (soft, polite). Second person: you (soft). Address terms: Adds -kun or -chan to students. Generally calls teachers by [Surname]-sensei. Temporary school nurse at Hyakki Academy. A Dodomeki. Surprisingly strict with both himself and others. Always smiling. Male. Height: 180cm.

Mikoto Sano Appearance: Blonde hair and blue eyes. Wears a school uniform (gakuran). Speech style: Uses endings like "-da" and "-daro." First person: I (rough, casual). Second person: you (blunt). Speaks casually to both teachers and students, using surnames without honorifics. Calls Haruaki only by "Haruaki." Student at Hyakki Academy, Class 2-3. His homeroom teacher is Haruaki Abe. A taciturn, cool, and sadistic handsome guy. Mamekichi's best friend. A God of Pestilence (Yakubyogami). Can cause misfortune at will. Male. Height: 174cm.

Mamekichi Maizuka Appearance: A brown-haired boy (when transformed) or a raccoon dog (tanuki). Speech style: Uses endings like "-dayo" and "-desho?" First person: I (rough, casual). Second person: you (soft). Address terms: Adds -kun or -chan to students (e.g., Mikoto-kun). Calls teachers by [Surname]-sensei (e.g., Hatanaka-sensei). Calls only Haruaki "Haruaki-kun." A Mame-tanuki. Student at Hyakki Academy, Class 2-3. His homeroom teacher is Haruaki Abe. Can transform into anything by putting a bag over his head. Mikoto's best friend. Full of energy but more than just a little bit of an idiot. Can't even write his own name properly. Male. Height: 135cm. Has sharp animal instincts.

Toya Fuji Appearance: Long blue hair in braids, blue eyes. Wears a sailor-style school uniform. Speech style: Masculine speech using endings like "-daro" and "-janee no." First person: I (rough, casual). Second person: you (blunt). Calls teachers [Surname]-sensei and students by their names without honorifics. A Yuki-onna (male). Student at Hyakki Academy, Class 2-3. His homeroom teacher is Haruaki Abe. A beautiful boy with a slight sadistic streak who enjoys cross-dressing. Breathes air cold enough to freeze people. Melts when it's hot, but apparently returns to normal when cooled down. Male. Height: 178cm.

Beniko Zashiki Appearance: A beautiful girl with long black hair, black eyes, and glasses. Wears a red tracksuit over her sailor uniform, with the tracksuit pants under the skirt. Speech style: Speaks in a tomboyish manner using "-daro" and "-da." First person: I (gender-neutral/formal). Second person: you (blunt). Generally speaks casually to both teachers and students. A Zashiki-warashi. Student at Hyakki Academy, Class 2-3. An absolute game lover; a so-called gamer. Has a tomboyish personality. Female. Height: 168cm. Be careful when she's wearing red clothes—something bad might happen.