Spoiler note: this post covers all 17 volumes of the manga. The ending sits in the last section, after a divider, so you can stop before it. If you only watched the anime, a lot of this will be new to you.

Short answer: no. Kei Nagai is not cold. He is earnest about one goal, and he will do almost anything for it, including things that look heartless.

I did not always think so. In my last post about Ajin, I wrote that Kei “reads as almost a psychopath: cold and calculating,” and that this was what I found cool about him. After going back through all 17 volumes, I think I read him wrong.

(I’m using “psychopath” the way fans do, not as a diagnosis.)

Why so many people call him cold

Ajin is about people who cannot die. Kei Nagai is a high school student who wants to be a doctor, until a truck hits him on the way home and he comes back to life. After that, the state hunts him.

The anime streamed on Netflix in 2016. On anime forums back then, viewers called Kei “a high-functioning sociopath” and worse. A few noticed that he wasn’t as heartless as he looked. The anime never really settled it. Fan guides say its second season goes its own way, while the manga kept going until 2021.

The label is not only something fans made up, though. The story gives it to him. In the Japanese edition, three chapters in a row in Volume 3 share the title Hontō no Nagai Kei, “The Real Kei Nagai.” That is where his younger sister Eriko tells her side. She describes a brother who is cold, and who acts for his own benefit.

Some context Japanese readers take for granted. In Japan, you apply to medical school straight out of high school. It is a six-year program, and the entrance exams are among the hardest in the country. So a high schooler who wants to be a doctor is not dreaming about someday. He is already in the race. In Volume 2, Kei’s classmates describe him as an odd guy whose hobby seems to be studying.

That is the kind of student Kei is when the story starts. Keep it in mind. A lot of what looks cold is what that race looks like from the outside.

The case for “cold” is real

I am not going to pretend otherwise.

In Volume 5, Kei needs an ally with power. He looks into the officials of the government’s Ajin committee and picks Yu Tosaki. His reason is a weak point: Tosaki’s fiancée lies unconscious in a hospital. Kei walks into that hospital to negotiate. He says that if he is captured, he cannot promise what his black ghost (the creature an Ajin can summon) will do to the people nearest him, and he points at her. Tosaki, furious, says he will kill him.

In the middle volumes he says things like “I don’t care how many people die” (Volume 8) and that the value of a life changes with the situation (Volume 9).

If you stop reading here, “psychopath” sounds fair. I stopped here the first time.

What the label leaves out

He asks about his sister first. In Volume 2, Kei gets three questions when he meets Sato’s group. His first is about Eriko. Koji Tanaka, who is on Sato’s side, grades him on it: fail. Asking about his sister first, Tanaka says, shows he has not cut his ties with human society.

Think about that. The villains have a test for coldness, and Kei fails it.

He tries to save the people who experimented on him. In Volume 3, Sato’s side raids the lab where Kei was cut up and studied. Kei asks them not to kill the researchers. He even offers to be a decoy. Afterwards he mutters that you should never go around helping people.

That line is how he sees himself. What he did is something else.

He pushes away the people he cares about. In Volume 1, Kei decides he cannot drag his old friend Kaito any deeper into his trouble. In Volume 10, Eriko again calls Kei cold, this time over Kaito. Their mother answers her. A former emergency-room doctor, she says Kei decided at nine to become a doctor, and that in order to do it he cut Kaito loose. To care about something, she says, is to see it through, and that sometimes means cutting things away. He gives everything he has, so you should not judge him with the single word “cold.”

The manga answers its own label, and it does so through his mother.

He dresses up feelings as logic. In Volume 10, Kei walks back into a fight he says cannot be won. His explanation is that he thought hard about how to raise a zero percent chance as high as possible, so it is a perfectly logical act. Kou Nakano laughs and asks who the real idiot is.

A cold person would not need the explanation.

Earnest about what?

Kei is earnest about his goal, and his goal is more specific than “survive.”

In Volume 2, a classmate remembers why Kei wanted to get into medical school: to cure his sister’s rare illness. So the sister who comes first in Tanaka’s test and the career he never lets go of are the same thing. Both come from one decision.

Notice what he does not want. In Volume 11, he says he has never once resented being an Ajin. He does not want to be an ordinary human again. He wants his path back. Being an Ajin is the thing that got in the way, and he works around it.

There is a small moment in Volume 5 I love. After everything, a car display shows September 3, and Kei realizes summer vacation is already over. Only a student thinks like that. Under the threats and the plans, he is still counting school days.

When “cold” and “kind” both fit one person, I stop asking which is true. Both are earnestness aimed at the same target. If the goal needs a threat, he threatens. If the goal needs him to spare a researcher, or to walk back into a fight, he does that.

Sato plays. Kei does not.

Sato, the Ajin who declares war on Japan, is the best way to see the difference.

In Volume 1, Sato asks Kei if he likes games. If you have a hundred lives in a game, he says, you can come back a hundred times. In Volume 10, we see Sato as a young man in an arcade in the United States. He says life does not work like a game. Then he is shot, finds out he cannot die, and treats it like a coin dropped into the machine. Continue? Yes.

He keeps that attitude to the end. In Volume 17, he tells Kei the fight was fun, and that being an Ajin brings a kind of pleasure. People, a country and his own death are all part of the game to him.

Kei answers in the same scene that he hates doing anything just for fun. Everyone around him is serious, he says. For him this was never a game.

That is why Kei can look cold next to a man like Sato. Sato enjoys himself, and Kei never does. Kei is the one who is not playing.

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What the anime never showed: the last volumes (spoilers)

If you have not finished the series, leave this closed.

Show the spoilers (Volumes 15 to 17)

In Volume 15, Kaito steps in to help Kei one last time, against Kei’s warning to stay out of it, and Kei breaks down over him. Right before that, he had been telling himself that letting Sato leave the country was the best outcome.

I have never seen a cold person work that hard to talk himself out of feeling something.

And at the very end, when someone asks Kei what he will do now, his answer is the same one he settled on at nine: he will aim to be a doctor.

So, is he a psychopath?

No. I read him wrong the first time, and I think the story invites that. Eriko says he is cold, and Kei says it about himself.

He is a student with one goal who will not drop it, and who looks cold when the goal asks for something hard. The next time you read Ajin, watch what he does right after a cold line.

Should you read the manga if you watched the anime?

Yes, especially if Kei bugged you. The manga gives him a different ending from the anime’s. Fan guides suggest starting around Chapter 22, in Volume 5, where the two versions split. The English edition is published by Vertical.

This is the second Ajin post in my series about reading modern Japan through manga.

Sources

• Wikipedia: Ajin: Demi-Human (publication, anime and English edition)
• MyAnimeList forum: Ajin Episode 8 discussion (2016)