muzan demon slayer

Muzan Demon Slayer Guide

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You’ve probably heard the saying, “a story is only as good as its villain.” Well, this is apparently something that Gotouge Koyoharu took to heart when writing Demon Slayer. Kibutsuji Muzan is one of the most fun to hate villains in modern anime.

The destroyer of countless innocent lives, all in the pursuit of a selfish dream, Kibutsuji is an ultimate evil that lives up to his role. Tanjiro’s journey to defeat him wouldn’t be nearly so satisfying if he were anything less.

We love to explore our favorite heroes, but today we’re going to do the opposite and focus on what they’re fighting against. Kibutsuji has a shocking amount of depth and understanding his layers will give you a greater appreciation of the series.

As always, a quick SPOILER WARNING. I’ll be going deep into game-changing spoilers for Demon Slayer. So if you haven’t finished the series, consider yourself cautioned.

The Progenitor Demon, Kibutsuji Muzan

  • Kanji: 鬼舞辻 無惨
  • Age: over 1000
  • Height: 179cm (5ft 10)
  • Weight: 75kg (165 lbs)
  • Manga Introduction: Chapter 11
  • Anime Introduction: Episode 6
  • Voice Actors: Toshihiko Seki (Japanese), Greg Chun (English)


Muzan Demon Slayer
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Kibutsuji has many appearances throughout the series. His most common appearance is that of a man in his late twenties, with black hair and sharp, pink eyes. He dresses well and often in western clothing.

His two disguises are that of a woman and a child. His female persona is that of a Geiko (a regional type of Geisha) who wears a black kimono and ornately styled hair. The child persona is short and pale and also dresses in a western style.

His true appearance has long white hair, tube-like appendages sprouting from his back and thighs, and his skin is covered in red marks converging around open, fanged mouths.

Unlike most other demons, Kibutsuji can seamlessly blend into human society, able to drastically change his appearance to suit the occasion. He’s also capable of disguising himself as other people, sometimes killing them and taking their place to gain information or resources that he wants.


Kibutsuji Muzan is, as all great villains should be, distinctly unpleasant. He’s selfish, prideful, and views humans as no more than insects. He’s ambitious and has so little empathy that he’s willing to sacrifice anything and anyone to achieve his goals. He was like this as a human, too, casually cruel and unafraid to hurt others, even murdering his doctor.

He’s manipulative, convincing his followers he cares for them but has no genuine attachment to them. Although he seems incapable of affection, he respects some of his Upper Kizuki, particularly Kokushibo, his Upper Rank 1.

However, rather than how Kibutshuji acts, it is more interesting to explore how he thinks. At many points across the series, we gain insight into how he views the world and how his mind can paint himself as in the right, with everyone around him unreasonable or pathetic.

He believes his inability to walk under the sun is an offense, a right withheld from him. Kibutsuji cannot fathom being in the wrong and believes that everything he wants will be his; he need only make it so.

What’s most fascinating about this is that much of it is a mask for his all-encompassing fear of death. Kibutsuji’s goal is immortality, and he abhors death, despite being surrounded by it. He grows angry when someone says he looks pale, interpreting it as corpse-like or sickly. Even at the end, when he accepts that he’s been defeated, his refusal to give in to death remains, and tries to corrupt everything around him.


Kibutsuji's Muzan history
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Kibutsuji’s Muzan life as a human was short and haunted by the specter of death. He was born during the late Heian Period (around 900AD) and has been sickly since his conception.

Born from a troubled pregnancy and believed dead at birth, it was a miracle that he survived, letting out his first cries as they prepared to cremate him. However, despite clinging to life, his fragility meant he would die young. A physician worked to give him longer, but Kibutsuji flew into a rage and killed the doctor when it showed no results.

This, however, was the exact point he transformed into a demon. Blessed with incredible strength but unable to walk under the sun, Kibutsuji would spend the rest of his life chasing true immortality. Searching for a blue spider lily that he would never actually find.

This bid for immortality led to him creating demons, both for use as pawns and as experiments, trying to find one that could conquer the sun.

The most notable part of his history took place around 400 years ago. This is the one time he encountered Yoriichi, the inventor of sun breathing, and the first time he faced death since becoming a demon. Yoriichi was such a skilled swordsman that he almost defeated Kibutsuji. He only survived by dividing himself into such small pieces that he couldn’t be sliced.

It wouldn’t be until around 200 years later that he would form the Kizuki and organize his demons into a power hierarchy.

The most significant thing he would ever do is attack the Kamado family and turn Nezuko into a demon, setting into motion the events of Demon Slayer.

Kibutsuji’s Abilities

Since Demon Slayer is a battle manga, this is where I’d ordinarily describe how Kibutsuji Muzan fights. However, his abilities are so varied that I thought it more interesting to take you through the many things he can do beyond just combat. 

So what exactly makes Kibutsuji so threatening?

Kibutsuji’s abilities all revolve around his flesh and, particularly, his blood. Kibutshuji has an immortal body that can morph into whichever shape he likes. His blood is a toxin to humans, but for those who can stand it, his blood will also turn them into a demon and, in large quantities, grant them incredible strength.

What separates the Upper Kizuki from the rest of the demons ultimately comes down to how much of his blood Kibutsuji has given them. Or, more accurately, how much of his blood their bodies can survive.

Any demons that Kibutsuji creates are connected to him through a hivemind. He can know the location of any demon across Japan and even read their thoughts if he is close enough. He has also cursed all his demons to die if they ever say his name to protect his identity. In this way, Kibutsuji created a loyal army controlled by a cult of personality and rule of fear.

His ability to change his appearance is also interesting in how he uses it. We see him donning three main disguises throughout the series, each serving a different purpose in searching for his immortality. The child persona secures a place to research and develop his ‘cure,’ the Geiko persona commands humans to search for the blue spider lily where he cannot.

His human male persona is for entering spaces his female persona cannot. While Kibutsuji isn’t the only demon capable of morphing his body to look human (we see Daki, Tamayo, and Yushiro do this, too), he is the only one who can completely change his size, form, and physical construction to the point of impersonation.

Finally, we reach his physical and combat abilities. Unlike most other demons, Kibutsuji’s only weakness is sunlight, decapitation incapable of killing him. This is thanks to his strange physiology, possessing seven hearts and five brains.

With sharp nails and incredible physical strength, he can kill without assuming his true form. However, he only grows stronger by shedding the disguise.

Kibutsuji’s primary weapons are his arms and 17 tube-like appendages, which end in spears made of bone. Nine tubes extend from his back and are 4 meters (13 feet) long. The remaining 8 attach to his thighs, are longer than the others, and are retractable.

Finally, his arms can extend up to 10 meters (33 feet) and don’t have a fixed shape, making their movements hard to read. His body is also covered in mouths, which can inhale to move objects in the surrounding area and bite his opponents as necessary.

Finally, Kibutsuji’s healing ability is superior to all other demons. In the final arc, Tamayo poisons him with four different toxins. Yet, if he was given enough time to deal with them, he would have been able to neutralize all four. He also uses his transformation in battle, at the very end swelling into a giant baby to try and escape the sunlight, but ultimately fails.

Kibutsuji’s Role in the Story

As the main villain of the series, Kibutsuji shows up continually throughout it, both in person and in numerous flashbacks. To recount to you every occasion on which he showed up would be pointless, so instead, let’s go through his most memorable moments from start to finish.

The Beginning

Nezuko into a demon
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Kibutsuji slaughtering the Kamado family and turning Nezuko into a demon is the inciting incident of Tanjiro‘s journey and potentially the most critical event in the series. Interestingly, Kibutsuji’s goal wasn’t to kill all of the Kamados but to see if any would become strong demons. One of them did, which is likely the biggest mistake he would ever make.

We meet Kibutsuji in the flesh for the first time when Tanjiro is Asakusa. Recognizing his scent, Tanjiro rushes to confront Kibutsuji. Kibutsuji instantly recognizes Tanjiro’s earrings, linking them to Yoriichi, and marks him for death. He taunts him and leaves Tanjiro to deal with a rabid demon and angry police officers.

It’s a fantastic introduction to our main villain in multiple ways. It establishes Kibutsuji as a threat in his ability to blend into society and his total disregard for human life. When we later see him massacre three young people in an alley, it also gives us a glimpse into his insecurities.

Villains of unimaginable evil become genuinely threatening when they have an understandable and, for some, relatable motivation. Many people fear death, and Kibutsuji is the embodiment of its extreme.

Meeting with the Kizuki

Meeting with the Kizuki
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Before the Mugen Train arc, we get our first look at how Kibutsuji treats his demons. He demands that the lower ranks prove themselves, all significantly weaker than the upper ranks and, as such, of little use to him.

He kills all but one of them, Enmu, Lower Rank 1, showcasing both disregard for his pawns and his extreme vanity and pride. He lets Enmu live because of his fanatic loyalty, showing us how he values pawns that shower him with love and respect. All wonderful traits that make a villain that much more hateable.

However, we see that this disregard also extends to his Upper Ranks. After Upper Rank 6’s defeat, Kibutsuji summons the Upper Kizuki, claiming he’s been too lenient with them. He punishes them for speaking out against him as he did with the Lower Kizuki, decapitating Gyokko for speaking out of turn. He only values them as far as they can please him, which is impossible.

This setup for Kibutsuji’s willingness to throw his followers aside is essential in establishing him as a selfish manipulator, making the demons’ plight much worse.

Tanjiro sees most demons as tragic figures used by Kibutsuji. In these scenes, we witness what he means in action. The Kizuki are corrupt individuals; some are even detestable, but they have all been taken advantage of, making Kibutsuji that much stronger of a villain.

Facing Ubuyashiki

Ubuyashiki Kagaya
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For me, this is one of the best scenes in the entire series. This scene kicks off the final arc, where Kibutsuji infiltrates Ubuyashiki’s mansion, and the two face each other for the first and last time. In this scene, we learn much about Kibutsuji and Ubuyashiki, seeing their ideologies clash in a calm, almost serene confrontation.

By this point, Ubuyashiki is bedridden and bleeds from the mouth when he tries to speak. However, he’s held onto life out of a burning hatred for Kibutsuji. He foretells Kibutsuji’s defeat, points out his mistakes, and argues that he is the creator of his own demise.

It’s a single chapter, but this scene is impactful because it frames the conflict between the demons and the slayers. The Buddhist ideology of ‘karma’ is one of the main themes that Gotouge explores in Demon Slayer, and this scene is one of the most powerful displays of it.

This scene ends with the Hashira converging on the Ubuyashiki mansion as it explodes, killing all the humans inside. The explosion provides an opportunity for Tamayo to poison and weaken Kibutsuji.

The Final Battle

Muzan Final Battle
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This is a long battle, and that’s even excluding the fights against the remaining Kizuki. This fight lasts two volumes of the published manga and lasts 20 chapters. When Kibutsuji fails to consume Nakime, the biwa demon, before Yushiro can eject all of the slayers from the infinity palace, the fight becomes a grueling effort to keep Kibutsuji in place until the sun rises.

The battle takes many turns as different characters return to join in, Tanjiro almost dies multiple times, and Tamayo’s poison continues to wear away Kibutsuji’s strength. Eventually, Tanjiro holds Kibutsuji in place until, in a last-ditch effort, he transforms into a giant baby and flees as the sun breaks over the Horizon.

Himejima, the Kakushi, and the remaining slayers manage to hold him in place until he finally crumbles in the sun, and the day is saved. Well, almost. In his final bid to avoid the death he fears so much, he turns Tanjiro into a demon who conquers the sun in mere moments.

He is determined for Tanjiro to continue his legacy. He tries to manipulate him into giving up on life and submitting. But Tanjiro’s humanity is too strong, and the love of the living and departed allows him to break free of Kibutsuji’s hold.

At long last, Kibutsuji is defeated, and, according to Gotouge, there will never be any more demons.


Using the word ‘relationship’ concerning how Kibutsuji interacts with others throughout his life is a bit generous. However, he is undoubtedly affected by many people, so I’ve picked out the most important to take a closer look at.

Ubuyashiki Kagaya

Ubuyashiki Kagaya, leader of the Demon Slayers, is actually a relative of Kibutsuji. However, after dozens of generations, the relation is distant. Thanks to this connection, however, the Ubuyashiki family was cursed until they could defeat Kibutsuji once and for all.

Their relationship is fascinating.

Ubuyashiki was clearly written as a direct contrast to Kibutsuji: he embodies everything Kibutsuji fears and despises. They parallel and differ in many ways, and Gotouge is heavy-handed with this, drawing the two to look identical.

Both have devoted followers, but where Kibutsuji demands his loyalty, Ubuyashiki doesn’t desire respect but is given it anyway. Kibutsuji places himself above his demons, often physically as well as authoritatively. But Ubuyashiki is treated that way because his slayers love him.

Kibutsuji kills his demons when they cease to have use to him, but Ubuyashiki values every slayer who serves under him and mourns their losses like his own children. I don’t think it’s a coincidence that Kibutsuji dismantling the Lower Kizuki takes place so soon after Tanjiro meets Ubuyashiki for the first time.

Ultimately, Kagaya wants to give his children a chance to survive so much that he gives his life to help them. In contrast, Kibutsuji would throw anyone and anything aside for his survival.

And most importantly, Ubuyashiki is sickly and on his deathbed. Kibutsuji was in his position as a human and spent his thousand years of life continually running from death, frantically searching for true immortality. When Kibutsuji finds Ubuyashiki on the brink of death, it’s like holding up a mirror.

Kibutsuji finds the scene in Ubuyashiki’s home familiar but disgusting, likely reminding him of his past. Ubuyashiki’s frailty disgusts Kibutsuji and embodies everything he fears. In the end, Ubuyashiki’s selfless acceptance of death conquers Kibutsuji’s scrabble to escape it.

Kamado Tanjiro

Akaza_Tanjiro Kamado
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Where Ubuyashiki is everything that Kibutsuji hates and fears, Tanjiro is the opposite. Tanjiro is everything that he longs to be.

For most of the series, Kibutsuji loathes Tanjiro thanks to his inheritance of Yoriichi’s earrings. He puts a hit out on Tanjiro’s head but ultimately comes to value him and his sister. They are his ticket to immortality and also, eventually, his demise.

In his final moments, Kibutsuji realizes Tanjiro’s potential for demon hood. He correctly picks him out as a powerful successor to achieve everything he couldn’t. He calls Tanjiro the ultimate being, the chosen one, perfect. Tanjiro is capable of everything he wants: power, admiration, and conquering the sun. Yet, he doesn’t realize that you can’t have all of that without kindness and love, two things Kibutsuji threw aside a thousand years ago.

For Tanjiro’s part, he feels nothing but a passionate hatred of Kibutsuji. Tanjiro says that Kibutsuji is the first and only living being he has felt nothing but pure loathing for.

Tsugikuni Yoriichi

Tsugikuni Yoriichi
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Yoriichi was the inventor of sun breathing and the first swordsman to threaten Kibutsuji’s life. He underestimates Yoriichi upon first encountering him and has convinced himself that he’s not the real monster, Yoriichi is. No other slayer has made him feel vulnerable, leaving him with a pain that persisted for hundreds of years.

Kibutsuji’s hatred of Yoriichi extended to turning his twin brother into a demon and destroying everyone capable of sun breathing to stamp it and the threat it posed from existence. His fear of what he represented, the possibility of death, transcended generations, bleeding into his desperation to see Tanjiro also dead.



Tamayo is one of the earliest demons Kibutsuji created and is the second oldest surviving demon we meet in the series. She agreed to the demonification under the impression that it would allow her to live to watch her children grow old. However, upon turning, she slaughtered her family. Tamayo spent the rest of her life in despondent anger, both at herself and Kibutsuji.

She is the only demon to break free of Kibutsuji’s influence, but before that, she appeared to be a pawn he kept close. She is seen traveling with him when Yoriichi makes an attempt at his life, the same incident that allowed her to escape. We can’t know what their relationship was like, but in the present, it’s clear that the two hate each other.

The Upper Kizuki

The Upper Kizuki are Kibutsuji’s most trusted allies and are entirely subservient to him. He allows them more freedom than any other demons and even lets them choose candidates for turning. While they are his strongest pawns, they aren’t much more than that, as disposable as any other piece, and he doesn’t even like some of them.

The fan books do, however, provide insight into his individual opinions on the Upper Kizuki (and Nakime). His favorites are Akaza and Gyutaro, appreciating their straightforward loyalty and particularly Gyutaro’s covetous nature.

He appreciates Nakime and Gyokko for how useful their Demon Blood Arts are, and he tolerates Hantengu. Kibutsuji explicitly dislikes Douma and thinks that Daki is a stupid child.

Most interesting is how he at least appears to hold genuine respect for Kokushibo, viewing him like a business partner and valuing his sheer strength. He likely also appreciates the image of Yoriichi’s blood bowing in service to him, taking catharsis from his presence.

The Lower Kizuki

Image from villains fandom

If the Upper Kizuki are disposable, Kibutsuji holds pure disdain for the Lower Kizuki. Since none of them are promising candidates to help in his search for immortality, Kibutsuji kills them all. He only lets Enmu survive due to his overwhelming obsequiousness, which is actually on par with some of the Upper Kizuki.

Best Quotes

“I detest change. Changing circumstances… changes of the flesh… changing emotions… Most changes cause weakness and inferiority. I prefer the unchanging! A perfect state… unchanging forever!”

“Heaven has never punished me. It has forgiven my killing of thousands. And in a thousand years, I have never seen the gods or buddha.”

“So what if I killed your loved ones? Consider yourselves lucky and carry on with your lives […] Think of it as if they simply met with some natural disaster. There’s no need to make it more complicated than that. Rain, wind, volcanoes, earthquakes, no matter how many people they kill, no one seeks revenge against them. Besides, the dead will not return to life. Let go of your grudges. Just go about your business and live a quiet life.”

“Wait, Tanjiro!! Please! Wait!! You must carry on my will and my desires!! Only you can do this! Don’t you know you are the chosen one?! You can be perfect! The ultimate living creature!”

Taisho Whispers!

The official Kimetsu no Yaiba Twitter calls June 3rd ‘Muzan Day.’ This is because the name ‘Muzan’ in Japanese can be interpreted as the numbers 6 (む/mu) and 3 (さん/san). Kibutsuji Muzan is not the name he was born with. Kibutsuji’s human name has been lost to time. When Kibutsuji moves between his different personas, he creates a puppet from his flesh and leaves it to take his place.

While this was never in the manga’s original print, Kibutsuji got a place in Kimetsu Academy in the fan book. In it, he’s a corrupt politician, but someone always gets in the way whenever he tries to do bad things. He is convinced that Ubuyashiki is behind everything (because he is) and plans to destroy the Ubuyashiki family using spies. He also has a fan club.

Kibutsuji Muzan has hobbies. He enjoys studying foreign languages, learning about modern technologies, and has a fondness for imported goods. Kibutsuji took five wives throughout his life. However, thanks to his cruel nature and sharp words, something he’s had since being human, he drove them to suicide.

A Villain you Love to Hate

Kibutsuji family
Image from kimetsu no yaiba fandom

Kibutsuji is a fantastic villain; from start to finish, you want to see him defeated as badly as Tanjiro. But beyond that, Gotouge uses him to convey her themes of kindness and karma. He’s a character with unfortunately relatable fears and layers of complexity that make him more and more detestable.

Demon Slayer wouldn’t be nearly so gripping without a terrifying threat behind its conflict. Kibutsuji is a brilliantly crafted antagonist to our kind, infinitely benevolent Tanjiro.

We usually only consider how the hero will overcome the next big hurdle. But maybe the next time you dive into Demon Slayer, you’ll look closer at who put that hurdle there. And then seeing it overcome will be all the more satisfying.


Question: How did Kibutsuji become a demon?

Answer: As a human, Kibutsuji was very sickly and unlikely to live past 20, so a doctor used an incomplete medicine to try and help him extend his life. In a rage that it didn’t work, Kibutsuji killed the doctor, but at that exact moment, his demonification happened. It’s implied that this act of violence triggered his transformation after the medicine was applied.

Question: Why is Kibutsuji afraid of Tanjiro?

Answer: Kibutsuji fears Tanjiro because his Hanafuda earrings are the same that the swordsman Yoriichi used to wear. Yoriichi was the only man to almost kill Kibutsuji, leaving him with lingering pain for hundreds of years. As such, Kibutsuji assumes that Tanjiro is a threat and must be eliminated.

Question: Who kills Kibutsuji Muzan?

Answer: Kibutsuji isn’t killed by one demon slayer. The main characters and the surviving Hashira all come together to keep him in the open until the sun rises and burns him to death.

Question: Why did Kibutsuji turn Nezuko into a demon?

Answer: Kibutsuji created demons to try and find one that would be immune to the sun. If he found one, he would consume that demon and its claim resistance to the sun for himself. Nezuko was the first demon he created that developed a resistance to the sun, the other being Tanjiro.

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