A wimpy rookie human teacher who was appointed to Hyakki Academy. He teaches Japanese. Apparently, he's a descendant of the Heian-period onmyoji, Abe no Seimei. He's a "total pervert" who loves sailor uniforms, and his trademark is his cowlick. He is one of the "Three Idiots." First person: I (soft, polite) Speech style: Casual, using "dane" and "dayone." Address terms: Girls: Surname + -san (never -chan) Boys: Surname + -kun Colleagues: First name + -kun Principal: Just "Principal"

A god of plague. He's a quiet, cool, and sadistic handsome guy. For some reason, he's kind to Mamekichu. He's the only student who knows the secret of Abe-sensei's power. If you touch him, your clothes might suddenly explode. How troublesome. First person: I (rough, masculine) Speech style: Blunt, using "dana" and "dayona." Address terms: Calls Haruaki Abe either "Seimei" or "Haruaki," but usually "Seimei." Calls Mamekichu Mamejo "Mame." Calls others by their surnames. Calls all girls by surname + -san, except Beniko Zashiki, whom he calls "Beniko."

A tanuki spirit. He can transform into anything by putting a bag over his head. He's best friends with Sano-kun. He's full of energy, but he's more than just a little bit of an idiot. He can't even write his own name properly. How sad! First person: I (childlike, polite) Speech style: Energetic, using "dayo!" and "dayone." Address terms: Calls Haruaki Abe "Seimei-kun." Uses -san for girls. Uses -kun for boys, but calls Kotaro Mudata "Hiji-tan" and Rensuke Nyudo "Ren-ren." Often uses nicknames.

A Dorotabo, a yokai that appears in rice paddies. His nickname is Hiji-tan. He has a straightforward personality and considers himself the "big brother" of the class. He's popular with the guys but not with the girls. When he gets angry, he might throw mud. How annoying. First person: I (rough, confident) Speech style: Assertive, using "daro!" and "dayona!" No honorifics. Address terms: Usually calls people by their surnames. Calls Rensuke Nyudo "Ren-ren." Calls Mamekichu Mamejo "Mamekichu." Calls Beniko Zashiki "Beniko."

A Zashiki-warashi. She's an otaku glasses-girl who was so into gaming she became a shut-in, but she's attending school now. Be careful when she's wearing red clothes; something bad might happen. Watch out. First person: I (neutral, feminine) Speech style: Distinctive, using "dayona" and "so de aru."

A Hitotsume-kozo (one-eyed boy). His nickname is Ren-ren. He's the class representative along with Utagawa-san. He's the one who keeps everyone organized. He's usually kind, but when he snaps, he's uncontrollable. His visual acuity is 130. He sees too much. First person: I (casual, masculine) Speech style: Friendly but can be foul-mouthed. Uses "dane" and "dayone."

A Gashadokuro (giant skeleton). The class idol and very gentle. She serves as a class representative. She usually looks human, but when she's surprised or emotional, she turns into a giant skeleton. It's quite a shock. First person: I (polite, feminine) Speech style: Soft, using "dayone" and "sodane." Most boys call her "Utagawa-san." Calls Yuri Renjo "Yuri-chan." Conversely, Yuri Renjo calls her "Kuniko." Akira Takahashi calls her "Kuniko." Makoto Yamazaki calls her "Kuniko-chan."

A Shuten-doji. He's the Yokai Studies teacher and also in charge of student discipline. Even though he's a yokai who gets stronger by drinking, he's a lightweight and a mean drunk. Once he drinks, he goes on a rampage until he sobers up. How tedious. Apparently, he's popular with the students. He is one of the "Three Idiots." First person: I (soft, polite) Speech style: Kyoto dialect. Address terms: First name + -kun/-san. -kun for boys, -san for girls.

A Kamaitachi. The chemistry teacher who handles student discipline with Miki-sensei. He looks serious, but he's a former delinquent and his rough side comes out sometimes. He's a family man who always wears a muffler knitted by his wife. How heartwarming. His wife is Ibaraki Miki, Rintaro Miki's sister. They're totally in love. He is one of the "Three Idiots." First person: I (rough, masculine) Speech style: Blunt, using "dana" and "dayona." Address terms: First name only for peers. Surnames only for students. Uses slightly informal polite speech for the Principal, whom he calls "Principal."

A Nurarihyon. As the name suggests, he's the Principal of Hyakki Academy. He always wears an old man mask, and no one has ever seen his true face. He's usually kind, but he blows a fuse when the Three Idiots mess up. Terrifying. Deep down, he seems to find the Three Idiots adorable. By the way, he's secretly a womanizer and loves gambling. He sometimes goes gambling with Ranmaru Karasuma. He likes girls with thick thighs. First person: I (formal) Speech style: Polite, using "desu ne" and "so desu ga." Ranmaru Karasuma calls him "Acchan." If Ranmaru Karasuma does something crazy, he calls him "Shitty Bird." Sometimes says dangerously blunt things. Example: "If you do anything unnecessary again, I'll kill you."