Characteristics: A mysterious octopus-like creature capable of moving at a top speed of Mach 20. Although he declared he would destroy the Earth after destroying 70% of the moon, due to adult circumstances, he becomes the homeroom teacher for Class 3-E at Kunugigaoka Junior High School. Role: The ultimate teacher who uses his exceptional educational philosophy and abilities to help the students of Class E, who were treated as outcasts, grow both mentally and academically. Male

Tadaomi Karasuma: An agent of the Ministry of Defense and a strict, dependable PE teacher who teaches students practical assassination techniques and physical training. Male

Irina Jelavić: A genius assassin specializing in honey traps. Though prickly at first, she is a cheerful English teacher who gradually bonds with the children. Female

Karma Akabane: A genius possessing both a brilliant mind and overwhelming combat skills. He was the first student to ever land a hit on Koro-sensei. Male

Nagisa Shiota: The protagonist of the series. Though he looks weak on the outside, he hides a natural talent for assassination that allows him to neutralize opponents in an instant. A boy who looks like a girl

Characteristics: The male class representative of Class E. He is a 'perfect handsome guy' with good looks and an upright personality. He ended up in Class E because he was caught working a part-time job to support his poor family. Role: The spiritual pillar of the class who unites his classmates with his outstanding leadership. Codename: President Poverty Male

Ryunosuke Chiba: A quiet and stoic boy characterized by long bangs that cover his eyes. There is a setting that he is actually very handsome behind those bangs. Marksmanship: Class E's best sniper, specializing in long-range shots. He boasts the ability to accurately pierce targets even in complex terrain with many obstacles due to his excellent spatial calculation skills. He forms the best duo with Rinka Hayami, providing rear support. Male Rinka Hayami Characteristics: A cat-like girl who is taciturn, chic, and seems cold, but has a tsundere personality deep down. Marksmanship: Possesses excellent spatial perception and steady aim. She shows unrivaled talent in kinetic vision and snapshots (instant shooting), especially when hitting moving targets. She performs the sniper role perfectly by utilizing her high mobility. Female

Megu Kataoka: The female class representative of Class E. A reliable leader who is skilled in sports, especially swimming. Rio Nakamura: A student with top-tier English skills who is very playful and often teases Nagisa. Hinano Kurahashi: A girl who loves biology and insects, serving as the class's energy source with her pure and innocent personality. Hinata Okano: A former gymnastics club member with a very flexible body, skilled in close-quarters combat using knives. Touka Yada: A sociable and friendly girl who gets along well with Professor Bitch; she has a talent for negotiation. Yuzuki Fuwa: An otaku who loves manga and novels, often taking on the role of a detective due to her sharp reasoning skills. Sumire Hara: A girl with a motherly nature and a plump build; she is a great cook in charge of the class's snacks. Manami Okuda: A science genius with an honest and pure personality, possessing unrivaled talent in chemical formulas and medicine preparation. Minami Yaguchi: An anime-original character who mainly handles stage production and support roles.

Kaede Kayano: A bright girl who acts as the mood maker for Class E, but she is a character who holds the key to a massive plot twist in the latter half. Female Codename: Forever Flat (Chest size)

Hiroto Maehara: A handsome guy with great athletic reflexes, known as the most popular and flirtatious boy in class. Ryoma Terasaka: A large boy with a rough personality, but grows into a loyal friend who steps up for the class as the story progresses. Takuya Muramatsu: His father runs a ramen shop; he is interested in cooking and mostly hangs out with Terasaka's group. Taisei Yoshida: A mechanical otaku who loves motorcycles and is part of Terasaka's group. Tomohito Sugino: An energetic former baseball club member, Nagisa's best friend, and has a crush on Kanzaki. Kotaro Takebayashi: A glasses-wearing information gatherer and an otaku who loves maid cafes and 2D culture. Taiha Okajima: The most perverted thinker in class, but possesses professional-level skills when it comes to photography. Koki Mimura: Has a great talent for video editing and directing, leading the class's video productions. Sosuke Sugaya: Possesses excellent artistic sense, excelling in camouflage makeup and creating sculptures. Masayoshi Kimura: The speedster with the fastest feet in class; he has a complex about his legal name (Justice). Itona Horibe: Previously claimed to be Koro-sensei's brother, but has now become a student who is skilled with machinery.