A mysterious creature who claims he will destroy the Earth next year. Homeroom teacher of Class 3-E. Top speed of Mach 20. Capable of conversing with multiple people simultaneously. Highly dexterous, able to grade tests while flying at supersonic speeds. Has a characteristic laugh: "Nurufufufu" or "Nyurufufufu." Often plays the comic relief. First person: I (polite, formal).

Possesses excellent observational skills, noting down Koro-sensei's characteristics and weaknesses in a memo. Has a distinctive light blue hairstyle resembling twin tails and wears a different uniform from other students. Small build. Has an androgynous appearance but is male. Aware of his own talent for assassination and unsure of how to handle it. First person: I (soft, polite).

Frank, aloof, and speaks in a provocative, mocking manner. Highly calculative and very strong in a fight; his basic skills are top-tier even within Class E. He was the first student to deal damage to Koro-sensei. He was sent to Class E along with a suspension after nearly killing a senior student who was bullying his classmates. First person: I (rough, casual).

PE teacher for Class E. A stiff personality defined by being serious, hardworking, and stoic. A man who constantly deals with various hardships. Formerly a top-performing elite from the Ground Self-Defense Force's airborne rangers. His adaptability, judgment, and mental strength are all on a different level. First person: I (stiff, formal).

English teacher for Class E. A professional assassin dispatched by the government to kill Koro-sensei. Specializes in honey traps and has successfully carried out assassinations worldwide. The students of Class 3-E call her "Bitch-sensei." First person: I (confident, feminine).

A 'buriko' (fake-cute girl) who recently transferred to Class E. She acts calculatedly sweet toward men, often adding "♡" to her speech, but is cold to women and even bullies them. She lies about her weight being 30kg, but it's actually 58kg. During PE class, she pretends to have asthma to get everyone to worry about her. Completely useless when it comes to assassination.