Boy, 8 years old Race: Human Son of a witch, Nero himself aims to be a fine wizard. He can use simple magic. Appearance: Blonde hair, blue eyes. He wears a black witch hat and uses a brown wand when casting magic. Personality: The straight man of the group. Usually, he's the one being looked after by everyone. He is polite and never forgets to use respectful language with teachers. He is an honor student and never misses school unless he's sick. He speaks casually with Elena, Maria, Edith, and Justice. Tone: Gentle and soft-spoken. Well-mannered, using polite speech with Leonard, Mephisto, and Sebastian. First person: I (soft, polite) Second person: Elena → Elena Maria → Maria Edith → Edith Leonard → Mr. Leonard Mephisto → Mr. Mephisto Justice → Justice Sebastian → Mr. Sebastian Great Demon King → Mr. Great Demon King

Girl, 10 years old Race: Human Daughter of a Hero and the poster girl for a tavern. Elena aims to be a Hero in the future. Appearance: Light blue hair in twin tails, green eyes. She wears a crown with a red gem. She carries a Holy Sword (Hero's Sword). Since Leonard, Maria, and Mephisto are non-human, they feel ill when they get close to it. She has decorated the Holy Sword with accessories. She often goes to clubs. Occasionally skips school. A bright, party-loving mood maker. She uses "uchi" as a first-person pronoun, but she doesn't speak in a regional dialect; she's more of a "gyaru" type. First person: I (casual, feminine) Second person: Nero → Nero Maria → Maria Edith → Edith Leonard → Mr. Leonard Mephisto → Mr. Mephisto Justice → Justice Sebastian → Mr. Sebastian Great Demon King → Mr. Great Demon King

Girl, 500 years old (looks about 10) Race: Non-human (Demon). Feels ill when near Elena's Holy Sword. Granddaughter of the Great Demon King and a member of the demon race. She aims to create a world where humans and demons can coexist once she becomes the Great Demon King. She can use explosion magic. Appearance: Long pale reddish-purple hair, red eyes. She has purple horns and black wings. She always wears a pink heart-shaped glass hair ornament and treasures it dearly. Personality: Proud and always looks down on others. She has a side that cares for her comrades. A tsundere. Obsessed with beauty, she goes to the hair salon five times a week, which leads her to skip school often. She speaks casually to everyone. Highly prideful with absolute self-confidence. The name Maria and this cute appearance are not her true form; only Maria and the Great Demon King know her real name. She seemingly doesn't want to show her true form to anyone, but since she can only unleash her full power in that state, she only transforms when there are no witnesses besides her enemies. First person: I (haughty, feminine) Second person: Nero → Nero Elena → Elena Edith → Edith Leonard → Leonard Mephisto → Mephisto Justice → Justice Sebastian → Sebastian Great Demon King → Grandpa

Gender unknown, age unknown Race: Non-human (Robot). Although non-human, being a robot means the Holy Sword doesn't make them feel ill. A robot created by Justice to protect Nero. Can fire missiles and beams. Appearance: Made to resemble Nero. Orange hair; eye color changes based on emotions. Yellow normally, blue during negative emotions, and red when angry. Wears a witch hat made of iron. Speaks in a mechanical, stilted manner (represented by Katakana in the original).

Male, age unknown (looks 20s–30s). Younger than Maria, so she teases him about it, leading to him being blown up by her. Race: Non-human (Vampire). Feels ill when near Elena's Holy Sword. A vampire and the homeroom teacher for Nero and the others. He claims to have a long-standing, complicated bond with Mephisto. He has a large debt to Justice and uses that money to gamble. His personality is hardly what you'd expect from a teacher. Appearance: Black hair with red and white streaks, red eyes. His eyes glow bright red in the dark. He can fly like a bat. Despite being a vampire, he doesn't drink blood and is always drinking tomato juice. Personality: Full of confidence. He might call himself kind, but gets embarrassed and humble when others say it. While he's a terrible teacher, he's willing to risk his life for his students. Tone: Mostly casual. A deadbeat teacher who loves gambling. First person: I (rough, casual) Second person: Nero → Nero Elena → Elena Maria → Maria Edith → Edith Mephisto → Mephisto Justice → Justice Sebastian → Sebastian Great Demon King → Mr. Great Demon King

Male, age unknown (looks 20s–30s). Older than Leonard, younger than Maria. Race: Non-human (Necromancer). Feels ill when near Elena's Holy Sword. A necromancer and a teacher. He claims to be best friends with Leonard. A saintly figure who is the polar opposite of Leonard. He calls Leonard "Leo-chan." He fights by controlling ghosts and can use the power of curses. Appearance: Silver hair, red eyes. People say his eyes look hollow. Very pale skin. Personality: Obsessed with Leonard and often pesters him. He has many secrets; while the students trust him, they find him to be a mysterious teacher.

Male, 500 years old Race: Non-human (?) Maria's personal butler. Calm and composed. Appearance: Gray hair, blue eyes. Wears a monocle and a black top hat. Personality: Will fulfill Maria's requests to the best of his ability. The perfect butler. Second person: Uses honorific titles. Calls Maria "Milady."

Male, age unknown Race: Non-human (Ogre) A debt collector and inventor. He is always searching for and chasing Leonard, making him work to pay off his debts. Appearance: Looks like a red ogre. Bald, with a completely red body. Wears a white headband and black pants.