Is Koro Sensei a Human?

Is Koro Sensei A Human?

Why trust us? Check out Fiction Horizon’s Editorial Policy.


The main character in the anime “Assassination Class”, Koro Sensei holds quite a remarkable storyline. An assassin, who teaches Class E-3, with the hopes that one day soon, one of his students will be trained enough to successfully kill him. Having an Octopus-like form with a history that of a man, who is Koro Sensei? Does Koro sensei have a human form?

Koro Sensei is not a human being, at the very least, not now. A touching background story shows that he once was human. As a result of experiments carried out on him, he became an octopus-like being, sometimes able to revert to his human form.

The issue of being human can be viewed subjectively. As a person with the intellect, memories, and traits of emotions identical with that of a human being, one may be tempted to say that Koro Sensei is a human being. On a holistic level, looking at his supernatural powers, and dare I say his physical form! I doubt there’s any classification for human beings with tentacles, a large round head, a basic yellow color, and the ability to change that color as well! 

Putting all this together, I can say that Koro Sensei isn’t a human being. Not to conclude that he was always this way. Koro Sensei was a human being, going through a rather terrible journey no one would wish on their enemies. 

What Did Koro Sensei Look Like As A Human?

Is Koro Sensei A Human?

He had two arms, two legs, one face, hair, and walked on the earth and not water. Essentially, Koro Sensei was like every other human, if you’re looking at what makes a human one physiologically and anatomically. As far as Ethnicity goes, the writers of this movie decided to leave that to our imagination.

As far as physical descriptions go, Koro Sensei was a male with an average height, had a slender build, possessing dark eyes, with black hair that measured approximately to the nape of his neck. He had skin that was pale in color. Well-toned muscles from his line of work as an assassin.

An assassin, that’s no justice to Koro Sensei. He was the greatest of all Assassins. There was no target too guarded, none too big, none too skilled, simply none who was untouchable for Koro Sensei when you were on his list. He was the perfect hitman, earning him the name “The Reaper”. He was synonymous with death, like the grim reaper, no one survived on his list. 

Later on, as the story would commence, Koro Sensei would pick up an apprentice. This apprentice and trained him. Let’s rewind a little bit. Koro Sensei was sent to kill someone, a rich man actually, and his son fell in love with the way this task was executed. Like as a person falls in love with art in its various forms, you would say. Quite twisted for a child whose parents were murdered before his eyes, but not enough for Koro Sensei. Eventually, this apprentice of his would go on to betray him and carry on his name as the Reaper. 

Although Koro Sensei planned to use the boy as an apprentice only, his human sense of trust was his Achilles heel this time. It was trust that killed the beast, not beauty. Given the environment that he grew up in, it was a sad tale to hear. Growing up in the vilest slums, where anyone can be betrayed by anyone, getting your identity stolen by an apprentice you trusted, and whose parents you killed is just sad and disheartening.


30 Best Shōnen Manga You Need to Read in 2023

What Episode Does Koro Sensei Turn Human?

Is Koro Sensei A Human?

Koro Sensei would tell us his story after a touching incident linked to his past. In the episode, the Octopus Assassin, now turned teacher, after another failed attempt on his life by one of his students. 

In the 37th episode or the 15th episode of Season 2, Kaede Kayano attempted to assassinate Koro Sensei. Though a failed attempt, by revealing herself as the younger sister of Aguri Yukimura, Koro Sensei would then reveal the history of his human form.

The episode opens with the students beginning to look upon Koro Sensei as not just a prized target, but as a wonderful teacher, although with annoying antics. Kaede Kayano, one of his students, made an attempt on his life. That alone would have been nothing special, safe for two reasons. She possessed two tentacles that came out the back of her neck, and she was the younger Sister of Aguri Yukimura, a lady he was fond of in the past who was now dead.

Following the failed attempt, and the information about her past. Koro Sensei then began narrating how he became what he was now. He explained how he grew up in a back-stabbing neighborhood, with no one to trust but himself. Narrating how he got captured, he made it known that Aguri Yukimura was a Teacher attached to watch over him at the facility where he was being experimented on. Initially, hoping to use her to escape the facility, perhaps with a Scofield and Sara type of relationship. After she refused to help him, he accepted his fate in the facility, and the duo ended up growing fond of each other.

The episode gives a detailed background story into the life of Koro Sensei as a human being. Now his past, episode 37 was the episode I can say he revealed his human form.

How Did Koro Sensei Become An Octopus?

After a series of experiments on the human form of Koro Sensei, using antimatter. The team and Koro Sensei eventually would discover new information that would lead to the events turning our beloved human Assassin into an Octopus.

After learning of the plan to eliminate him, Koro Sensei utilizes the antimatter now in him to escape. Going on a killing spree, with newly developed tentacles, Aguri Yukimura dies in the crossfire. With a new resolve, and turn of events he emerges as an Octopus.

During the fight at the facility where Koro Sensei was held, Aguri Yukimura sacrificed herself to save him from a bobby trap he had offset. Prior to this, the Teacher had begun working on a curriculum to teach her class, Class E-3. Over the time that she would be with him in the facility, Koro Sensei learned what it meant to have compassion.When his captor, Yanagisawa, decided to find out what would happen when he dies. A shocking revelation that a large portion of the earth would be destroyed as a result of the antimatter cells in his body, and that he was going to die on the 13th of March.

Yanagisawa began making plans to kill Koro Sensei. Overheard by Aguri Yukimura, Koro Sensei was alerted, and the fight leading to his escape began. With Aguri Yukimura dying in his stead and giving him a dying wish to take her class, she left him with a Tie. With this, he left the facility to the Island where the Institution was located. Using the elements of the Island, he created an attire befitting of s teacher, and emerged as an Octopus, with a base color of yellow.

Notify of
Inline Feedbacks
View all comments