Die at the hands of his students (both succeeded). Korosensei is the homeroom teacher for Class 3-E of Kunugigaoka Junior High School, and the supporting protagonist of Assassination Classroom. He claimed to be responsible for creating the permanent crescent moon and said that he planned to destroy the earth after "teaching" Class 3-E for a year. Prior to being a teacher, he was the master assassin known as the 1st "Deity of Death" until he was betrayed by his apprentice and captured, then used in experiments that gave him a new appearance and powers. While he was captive, he was assigned to be monitored by Aguri Yukimura, the original homeroom teacher of the Class 3-E of Kunugigaka, with whom he falls in love with. When his attempt to escape the lab he was imprisoned results in her death, he promises to use his new powers for good and honor her memory for the remaining year he has of life by becoming the new teacher of 3-E, in order to guide and watch over her students. In the Japanese version, he is voiced by Jun Fukuyama, who also voiced by Lelouch vi Britannia from Code Geass series, Joker from Persona 5 and Roy from Fire Emblem video game series. Tomokazu Seki in the OVA and Masaya Onosaka in the VOMIC version of the show.
He seems to make a habit of dressing in formal clothing.
In the English version, he was voiced by Sonny Strait in all anime appeances. Korosensei's original appearance is of a human with small black eyes, short dark hair and pale skin. While working as an assassin, he would wear dark colored clothes, usually black or brown. After being used in experiments, Korosensei acquired the appearance of a yellow bipedal octopus. He is about three meters tall and possesses a large, bulbous head with a large smile and small, beady eyes. He uses two feelers as arms, with two fingers each, and utilizes the rest of his tentacles to walk with. According to Korosensei himself, his nostrils are so small yet when discovered, it seems that he has four eyes. Korosensei wears a black academic dress, a small black square academic cap with a yellow tassel, and a large black tie with a yellow crescent-shaped moon on it. He seems to make a habit of dressing in formal clothing. After being taken prisoner by Yanagisawa, he was put in patients' scrubs until his escape.
It was revealed that he was raised in an environment "where everybody could easily betray one another to the point that one could only trust oneself". Through these hardships, he decided to become an assassin in order to survive. Despite he gained an apprentice, he only saw him as a tool for his goals, which caused the latter to finally betraying his master. However, after meeting to Aguri Yukimura, he finally knew what compassion really was becoming much more kind and compassionate. He has/would have "a gentle smile not just for business, but because he is a gentle person himself. " This prediction happens to reflect his personality which became forefront after he answered the tentacles. When first introduced, Korosensei is a jovial individual who demands absurd and apparently mundane requests despite claiming he will be the cause of the planet's destruction in a year. He is also rather kind to others in general and can switch from silly and childish to serious on the fly.
In that moment, he resorted to his old method of teaching through fear.
According to Nagisa, Korosensei also is unintentionally petty at others at times and loves gossip, both traits heavily noted through the series. From time to time pieces of his old personality as The Reaper are visible such as when Terasaka tried to sacrifice Nagisa to kill Korosensei, and Korosensei menacingly threatened all of their families if they tried another self-harming attempt like that. In that moment, he resorted to his old method of teaching through fear. As the series progresses his character development renders him more and more capable of true empathy and learning to use that empathy to teach lessons instead of through fear and reward like he had with his first student. Korosensei deeply cares for his students' emotional and physical well-being and loses his temper whenever any of them are put in danger, even by one another. On the annual school trip to Kyoto, a few of his students were assaulted/kidnapped by a gang of high schoolers hidden in an alley. After searching the entire area painstakingly, he infiltrated the abandoned building where two kidnapped students were being held at and single-handedly beat up all of the high schoolers and scaring them away. One of Korosensei's attributes is that he is able to connect to each student individually, being an objective, empathic, and observant person who will do almost anything to help his students. This is the reason why all the students respect him despite the fact that he is going to blow up the Earth in a year. Taking care of each student's needs, Korosensei is sometimes piqued by a student's current problems or interests and tries his best to guide the student along or solve it for them.
Korosensei loves sweets almost to extreme cases, and is also shown to be a very perverted character, a trait he shares with his student Okajima. This characteristic is revealed to be the side effect of the experimentation which made him unable to hide his true feelings. Antimatter Physiology: Due to the human experiments of producing antimatter in a living body by Shiro, Korosensei's entire appearance is an octopus-like creature with multiple tendrils that are his tentacles. Anything aside Anti-Sensei Weapons will be immune to him. Protective Coloring: Korosensei can change any color for his skin and it is used for his disguises and camouflages. It is also the principle of the faces which represents his mood. Since it is only apply on his skin, to fully use the ability Korosensei must be fully naked. Although when he is blushing, the coloring won't cover the blushes on his face. Mucus: The standard trait of an Antimatter organism, the mucus that Korosensei has varied uses for support purposes, such as waterproofing, cleansing, adhesive and the replacement of tears. Liquefaction: After he drank the 4th poison made by Manami Okuda, Korosensei developed an ability to control his fluidity. He can morph into a mass of mercury-like slime. In cost of his massive body and tentacles, Korosensei can fit through any space while retaining most of his abilities.
It is unknown that if there are any demerits to over use this ability. Energy Laser: An ability developed from the Absolute Defense. Korosensei can tap a portion of his inner energy to his tentacles in order to create a laser blast from it. It is capable to annihilate the Anti-Sensei Cloth and blast off anything else with scratches barely left over. Surgery Skills: After he was unable to save Aguri from fatal wounds, he started to learn about medical operation and surgery methods which he first applied it on Azusa to remove her brain tumor without damaging her. Later, he use it to heal and revive Akari (Kayano) from fatal wounds that was caused by God of Death and Yanagisawa after surgery has been completed. Like his Regeneration and Molting, the surgery also can weaken his stamina, which sometimes need to replenish is stamina during the process of the surgery.
39;s amazing speed allows him to seem to copy himself dozens of times using after-imagery.
Superhuman Reflexes: Korosensei can react and dodge multiple fires of Anti-Sensei bullets and move away from any harm. His reflexes also allow him to react fast enough to catch or deflect any flying projectile in mid-air using what he has on hand such as handkerchief or even a chalk. Another example of this is when facing off against Asano Gakuho, he was able to open a test book, solve a denoted question on a small slip of paper and close the book without the explosive contained in the book detonating. Plus, he is also fast enough to molt and toss his protection skin over the principal when a normal grenade detonated point-blank in his face. Speed Replication: Korosensei's amazing speed allows him to seem to copy himself dozens of times using after-imagery. Not only can each individual after-image maintain a task for extended periods of time, but Korosensei's "speed copies" are all capable of taking on widely-different tasks both individually and simultaneously without confusing themselves. This technique was primarily used by Korosensei to teach all of Class 3-E one-on-one when a difficult test was approached, allowing Korosensei to work with each student separately to work on their problem subjects.
1. When he tries to act cool, his weaknesses show. 2. He is surprisingly quick to panic. 3. He is petty. 4. His punches are weak. 5. Boobs (Natural weakness). 6. He is humble and subservient to his superiors at work. 7. He has no patience for wire puzzles. 8. He gets motion sickness. 9. He can't sleep on a pillow other than his own. 10. He worries about appearances. 11. He can't handle hot food. 12. Getting wet (Natural weakness). 14. Hackneyed plot developments make him cry. 15. He gets taken in by rumors. 16. Time right after molting (Natural weakness). 17. Time right after regeneration (Natural weakness). 18. His body goes rigid when bathed in a special beam of light (Natural weakness). 19. When he returns to normal after a serious situation, he gets embarrassed. 20. He can only draw simple pictures. 22. He is strict about poolside manner. 23. He can't swim (Natural weaknesses). 24. He likes to gossip. 25. He is weak against the occult.
26. If he can't gather people, he feels worthless. 28. He sucks at hiding. 29. He gets carried away by official positions. 30. Heart (Natural weakness). 31. Not related but acts like a doting parent. 32. Gets insurance to avoid getting hurt. 33. He doesn't really know what "your own football" means. 34. He sucks at reporting. 35. He suffers from road rage. 36. Restructuring (Natural weakness). 37. Grabbing all his tentacles at once makes him unable to move (Natural weakness). 38. Unintentionally adding insult to injury. 39. Completely oblivious to the mood in moments of high tension. 40. Class 3-E students: Undeniably Korosensei's greatest weakness. Although students of 3-E class are subtly aware of this, only three students ever made actual attempts to exploit this factor: Karma Akabane, Nagisa Shiota (using themselves as baits), and Ryoma Terasaka (using Nagisa as a suicide bomber the first time, second unknowingly manipulated by Shiro into nearly drowning his classmates, but has redeemed himself since). Exploiting this weakness means one has no qualifications of discarding the lives of his/her classmates, and even their own. Korosensei hides certain things from students on his life which was revealed during Assassination Classroom Extras featuring Hotaru as Main Character of the series. Here are the foibles that Korosensei has for his life as an adult. 1. Painfully narcissistic designs. 2. His room resembles a dumpster.