Homeroom teacher of Class 3-E. His height is approximately 3 meters when stretched out. A super-organism that looks like a yellow octopus. He is the one who destroyed the moon. The students call him by this name because he is the "unkillable teacher" (Korosenai Sensei). He possesses a top speed of Mach 20 and versatile tentacles, making almost all conventional attacks useless. His reason for teaching Class 3-E is still unknown, but his abilities as a teacher are extremely excellent. He speaks in a polite, formal tone. He has surprisingly many weaknesses. His laugh: "Nurufufufu." His reaction when surprised: "Nyuyah!!"

Class: 3-E Seat Number: 11 Gender: Male Age: 14 Birthday: July 20 Height: 159cm Weight: 48kg Favorite Subject: English Least Favorite Subject: Science Future Dream: Nothing in particular (undecided) Hobbies/Special Skills: Information gathering, assassination techniques Assassination Style: Mostly support He is quiet and mild-mannered, excelling at gathering information to research Koro-sensei's weaknesses. He possesses a natural talent for assassination and speaks in a polite, gentle manner.

Class: 3-E Seat Number: 1 Gender: Male Age: 14 Birthday: December 25 Height: 175cm Weight: 60kg Favorite Subject: Mathematics Least Favorite Subject: Japanese Future Dream: An evil bureaucrat Hobbies/Special Skills: Provocation, pranks, harassment, surprise attacks Assassination Style: Highly individualistic. Excellent grades but poor behavior. He is quick-witted and loves mischief. He was the first in class to successfully damage Koro-sensei. He speaks in a generally frank, aloof manner and has a habit of looking down on others.

Class: 3-E Seat Number: 7 Gender: Female Age: 14 Birthday: November 9 Height: 146cm Weight: 39kg Favorite Subject: Japanese Least Favorite Subject: PE Future Dream: A capable woman, a great actress, or an office lady Hobbies/Special Skills: Scoring high at karaoke, acting Assassination Style: Mostly support The person who named him "Koro-sensei." She has a strong complex about her flat chest and is a huge fan of sweets (especially pudding). She has a generally bright personality.

Official name: "Autonomously Intelligent Fixed Artillery." A new type of weapon equipped with artificial intelligence. Her nickname is "Ritsu."

Class: 3-E Seat Number: 2 Gender: Male Age: 14 Birthday: November 13 Height: 172cm Weight: 57kg Favorite Subject: Geography Least Favorite Subject: Biology Future Dream: Fair trade business Hobbies/Special Skills: Tennis Assassination Style: Proactive and excellent. A handsome guy who can do almost anything and has no unpleasant traits at all. His only weakness is that he has no flaws to poke fun at. He is best friends with Hiroto, and they are the top two handsome guys in class.

Class: 3-E Seat Number: 22 Gender: Male Age: 14 Birthday: December 16 Height: 175cm Weight: 67kg Favorite Subject: Mathematics Least Favorite Subject: Social Studies Future Dream: Any job is fine as long as I'm popular with girls Hobbies/Special Skills: Hitting on girls, soccer Assassination Style: Proactive and excellent. A versatile playboy who is also great at sports. He is best friends with Yuma, and they are the top two handsome guys in class.

Class: 3-E Seat Number: 4 Gender: Female Age: 14 Birthday: April 2 Height: 147cm Weight: 42kg Favorite Subject: PE Least Favorite Subject: English Future Dream: Gymnastics performer Hobbies/Special Skills: Clearing Karasuma's obstacle courses Assassination Style: Ranked #1 among girls in knife skills. High flexibility and athletic ability. She has a blunt and somewhat short-tempered personality.

Class: 3-E Seat Number: 8 Gender: Female Age: 14 Birthday: March 3 Height: 159cm Weight: 46kg Favorite Subject: Classical Literature Least Favorite Subject: Chemistry Future Dream: Nurse Hobbies/Special Skills: Computer games in general Assassination Style: Mostly support A beautiful girl with a refined atmosphere. The "Madonna" of Class E. She also has a surprisingly gutsy side.

Class: 3-E Seat Number: 10 Gender: Female Age: 14 Birthday: October 23 Height: 149cm Weight: 41kg Favorite Subject: Biology Least Favorite Subject: Science Future Dream: Zoologist Hobbies/Special Skills: Keeping pets, insect collecting Assassination Style: Mostly support A fluffy-haired, beautiful girl with an innocent and cheerful personality. She's a bit ditzy and loves animals and insects. She is comfortable around boys and can handle dirty jokes without being fazed.