Ajin Review: What Would You Do If You Could Never Die?

Quick Take

• An ordinary student discovers he is immortal and immediately becomes property of a government that has been torturing immortals for decades
• A manga about what happens when a person with no empathy gets unlimited power — and what it takes to stop him
• 17 volumes, complete, with one of the most unsettling antagonists in recent manga

Who Is This Manga For?

• Readers who want thriller pacing with horror elements and genuine philosophical stakes
• Fans of anti-heroes and morally complex protagonists who do not make comfortable choices
• Anyone interested in stories about what governments do with power they are not supposed to have
• Readers who want complete, finished series with a real ending

Content Warnings & Age Rating

Age Rating: M (Mature) Content Warnings: Graphic violence, torture (particularly of immortal characters who survive it), body horror, human experimentation

The immortality of Ajin means their torture is depicted in ways that would kill normal people. The manga does not shy away from what extended, repeatable suffering looks like.

Yu's Rating

Category	Score
Story Depth	★★★★☆
Art Style	★★★☆☆
Character Development	★★★★☆
Accessibility for Non-Japanese Readers	★★★★★
Reread Value	★★★☆☆

Story Overview

Kei Nagai is a high school student with one goal: become a doctor. He has no close friends, considers most people beneath his notice, and is entirely focused on his own success. When he is hit by a truck and walks away from it alive, he discovers he is an Ajin — one of a small number of immortal beings who cannot permanently die.

This is not good news. Ajin in Japan are immediately turned over to the government, which has been conducting secret research on their immortal bodies for years. Kei goes on the run and falls in with Sato, an Ajin who has decided to declare war on the entire Japanese government.

Sato is the villain of this story, and he is extraordinary — an elderly man with a cheerful manner and a military background who has been waiting decades for exactly this conflict. He has no ideology, no grand cause. He just enjoys the problem-solving, the strategy, the combat. Immortality means he can afford to play the game perfectly.

Kei, meanwhile, is not a hero. He is calculating, self-interested, and honest enough to acknowledge both of those things. Watching him navigate a war he didn't start, make choices that protect himself at others' expense, and slowly discover something like connection — it is not comfortable, and it is not supposed to be.

Characters

Kei Nagai — The least sympathetic protagonist you will root for anyway. His arc is about whether someone who does not naturally feel empathy can choose to act as though he does, and whether that choice eventually becomes something real.

Sato — One of the great manga antagonists of the 2010s. An old man who has found something he loves doing, and it is starting a war. His tactical scenes are some of the most satisfying in the genre.

Ko Nakano — Another Ajin, the opposite of Kei — emotional, impulsive, genuinely kind. Their partnership is the emotional center of the manga.

Tosaki — The government agent hunting Ajin, who turns out to be more complicated than his position suggests.

Art Style

Sakurai's art is functional but not distinctive — characters are clearly drawn, action sequences are readable, but it does not have the visual ambition of the best horror manga. Sato's scenes are often drawn with a particular flat energy that emphasizes his eeriness. The IBM (Invisible Black Matter) entities that Ajin can summon are visually interesting.

Cultural Context

Japan's government transparency around controversial research programs (Unit 731, various postwar incidents) gives the premise of secret government experimentation on a population a specific cultural resonance. The manga's portrayal of bureaucratic complicity in atrocity draws on a real Japanese tradition of examining institutional responsibility.

What I Love About It

Sato. I keep coming back to Sato. He is a villain who makes complete sense — his logic is coherent, his planning is meticulous, his cheerfulness in the middle of violence is genuinely disturbing — and he has no redemption arc and does not need one. He is what he is. The manga is smart enough not to explain him away.

The tactical scenes — Sato planning an assault, Kei planning a counter — are the most purely satisfying parts of the manga. It is a thriller that respects intelligence.

What English-Speaking Fans Say

Western readers often come to Ajin through the Netflix anime adaptation, which covers the manga's first arc. The manga is generally considered to have more detail and depth. Sato is consistently praised as an exceptional antagonist. The art style receives mild criticism. The ending divides readers — some find it satisfying, others wanted more.

Memorable Scene ⚠️ Spoiler Warning

Sato's one-man assault on the Ministry of Health building — moving through an entire building of security personnel, being killed repeatedly and regenerating each time, entirely unhurried — is one of the most efficiently terrifying action sequences in manga. It is where you understand exactly what kind of threat the heroes are facing.

Similar Manga

• Parasyte — Immortal/inhuman protagonist, similar philosophical questions
• Tokyo Ghoul — Hybrid existence in a world that fears you
• The Promised Neverland — Humans as prey, institutional horror
• Gangsta. — Augmented humans in a world with classified categories of people

Reading Order / Where to Start

Volume 1 from the beginning. The story builds steadily and rewards patience.

Official English Translation Status

Kodansha USA published the complete 17-volume series in English. All volumes are available in print and digital.

Pros & Cons

Pros

• Sato is one of the great manga antagonists
• Genuinely interesting moral questions about the protagonist
• Thriller pacing with tactical intelligence
• Complete series with a real ending

Cons

• Art style is competent but not remarkable
• Middle volumes can feel repetitive
• Supporting characters outside the core cast are underwritten

Format Comparison

Format	Notes
Individual Volumes	Standard release
Digital	Works fine; the art doesn't require large format
Omnibus	Kodansha has released some omnibus editions

Where to Buy

Get Ajin: Demi-Human Vol. 1 on Amazon →

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