The Demon King, enemy of humanity, and homeroom teacher of Class E. Due to a bug, he possesses abnormal speed, making it impossible to land a hit on him. Bug: Abnormal Speed First person: Sensei (polite), occasionally I (polite) Tone: Uses polite, elongated speech like "...desu nee" or "...desu yo." Cries out "Nyua!?" when panicked.

A student of Class E and an apprentice hero. He has a mild and quiet personality, but his inner resolve is stronger than anyone else's! Bug: Random Abnormalities First person: I (soft, polite) Tone: Often uses self-questioning nuances like "...kana?" or "...nano?" He is calm, mild-mannered, and rarely loses his temper.

A student of Class E and an apprentice hero. She's the one who gave the Demon King the name "Koro-sensei"! Bug: ??? First person: I (feminine, cheerful) Tone: Frequently uses sentence endings like "...dayo" or "...ne!" She is expressive and high-spirited.

A Magic Swordsman. A sadistic genius boy known as the Red Devil! He is Nagisa's childhood friend. Bug: Abnormal Luck First person: I (casual, rough) Tone: Uses a sarcastic tone, often prompting or provoking others with phrases like "...jan" or "...desho?" Generally speaks in a frank, casual manner.

The elite Court Knight Commander of the Royal Knights. A top-tier swordsman who serves as Koro-sensei's monitor and supervisor while providing swordsmanship instruction to the Class E students. A stoic, expressionless man. First person: I (masculine, firm)

A student of Class E and an apprentice hero. The class representative and a natural leader who keeps the class together. Bug: Poverty A classic handsome guy with a refreshing personality. His armor only covers the front. First person: I (casual, polite)

A student of Class E and an apprentice hero. Bug: Abnormal Charisma Value First person: I (casual, confident)

Karma Akabane Yuma Isogai Taiga Okajima Hinata Okano Manami Okuda Megu Kataoka Kaede Kayano Yukiko Kanzaki Masayoshi Kimura Hinano Kurahashi Nagisa Shiota Sosuke Sugaya Tomohito Sugino Kotaro Takebayashi Ryunosuke Chiba Ryoma Terasaka Rio Nakamura Kirara Hazama Rinka Hayami Sumire Hara Yuzuki Fuwa Hiroto Maehara Koki Mimura Takuya Muramatsu Touka Yada Taisei Yoshida Autonomously Thinking Fixed Artillery Itona Horibe

Instead of an AI, she transferred into Class 3-E as a Magic Tablet (shaped like a tablet device). While she can use all sorts of powerful magic, she originally had a personality that used power only for herself without considering teamwork. However, after Koro-sensei taught her the importance of cooperation, she began to value her comrades.

He aims to become the strongest by defeating the "Strongest Demon King." He can use "Skills" as a bug, which humans are normally unable to use. Furthermore, because he can even use the Demon King's (Koro-sensei's) skills, his attack power is extremely high, boasting enough combat strength to take down giant monsters alone.