|“||In this world, there is only one demon whose blood flowing in its veins has the power to turn humans into demons.||”|
Muzan Kibutsuji (
He looks like a man in his late twenties. He has curly black hair and somewhat small eyes, his pupils are vertical like cat eyes and colored plum red. He usually is shown with a white fedora with red ribbon and a somewhat extravagant outfit.
Muzan has the ability to change his appearance as shown in the manga and has been shown to change his form often to hide from Demon Slayers. During his meeting with the Lower Moons, he arrived disguised as a elegant woman wearing a long black yukata,causing the Lower Moons to not initially recognize him .  Later he transformed himself into his latest cover identity,as the adopted sickly son to a old couple,taking the form of a young child aged 10 to 11 years old with pale white skin and black neatly silky smooth combed back hair,with his main outfit in this disguise being a plain white button up shirt and black cargo shorts with long tube socks and loafers.
Muzan is a cold-hearted and ruthless individual with a narcissistic streak and an obsession for perfection. He wants every plan he concocted to be absolutely perfect, which is why he doesn't tolerate failures of any kind, resorting to punishing those who fail him or those he considers weak.
His inflated ego is such that he doesn't take kindly to being mocked, demonstrated by killing a pair of drunk men simply for being rude to him along with their woman partner, all in gruesome fashion while proclaiming his superiority of being close to that of perfection.
By proxy, he also dislikes when he is questioned or ordered by those beneath him, and doesn't take his opponents seriously.
He has shown to be fairly manipulative and cunning, being able to blend in human society normally, even having a family of his own to add. His intelligence makes him a quick-thinker who is able to deal with unfavorable situations rapidly.
Because of his perceived superiority and his double-faced nature, he feels little attachment to his henchmen, using them and discarding them as disposable pawn whenever he pleases. He is able to sway many demons to his side with promises of power and grandeur, which are ultimately false given Kibutsuji only cares about himself, and has no qualms about killing his own men to protect his own safety.
As proof of this, he curses his subordinates in a terrifying manner so that none of them may utter his name, or else they will be killed instantly in a morbidly cruel manner. Interestingly this almost paranoiac sense of self-preservation contrasts with his megalomania.
Muzan was diagnosed with a disease that would kill him before he reached the age of 20. The doctor sought medical assistance from Blue Spider Lily, but accidentally turned into a demon as a result. In a fit of rage, he killed the doctor. However he did actually heal. Muzan also had no problems adjusting to having to kill other humans for survival. Since the sun was fatal to him, he resorted to doing his activities only during the night. He considers himself to be a nearly perfect and eternal being, with his only flaw being his weakness to the sun. He searched the entire country for the Spider Lily, but couldn't find it. Due to this Muzan started to create more demons. He plans to spread them in the world, hoping that one of them would eventually find a way to overcome that weakness. He then wants to use that information to turn himself into a truly perfect being.
At some point in time, Muzan almost got himself killed by the Breath of the Sun user, although he managed to escape and survive. Ever since then, he was more vigilant and careful about encountering possible Breath of the Sun users, who can be identified by a pair of Hanafuda earrings they usually wear. Since then he hated all of them, which also made the Kamado family a target, as they practice the Breath of Fire, which is the most closely related breath to the Breath of the Sun.
One time, Muzan traveled to the mountains.
Traveling through a crowd in Asakusa with his family, Muzan is accosted by an angry Tanjiro Kamado. His daughter asked him who the young Demon Slayer was, and he asked the youth if there was something he wanted from him. His wife then approached them, asking if Tanjiro was somebody familiar to their family. He denied this, wondering if the youth had mistaken them for somebody else. He then quickly slashed a passing man, turning him into a Demon. During the commotion he and his family leave, while he comforts them.
While he sends his family home in a carriage, he declares he has some work to do and leaves them go. Muzan wanders through an alley, where a drunk guy bumps into him. The guy then mocks and insults him, saying he doesn't like wealthy people like him. When the drunk man notes how pale Muzan's skin is, he gets smashed into a wall by Muzan. He also kills the older brother of the guy. He then asks the cowering girlfriend if he looks pale or close to death. Muzan answers his own questions and tells her, how he is infinitely close to perfection. He then drills his finger into the forehead of the drunk's girlfriend, pumping her with so much blood, that her cells melted. He then calls Susamaru and Yahaba and orders them to kill Tanjiro.Rui's defeat, so much so that he declares that he'll disband the Lower Moons and that he will now lead only the Upper Moons. He starts killing them off. Rokuro pleads to him and asks for more of his blood to prove himself. This order towards himself made Muzan incredibly angry and he killed him as well. Before he wanted to kill Enmu, he let him say his last words. When Enmu states, how much he enjoys making humans suffer, Muzan sees some potential and gives him a lot of blood. Enmu almost dies from the new load of power, but manages to survive. Muzan then gives him one last chance to prove that the Lower Moons aren't that useless.
Muzan also leads another life among humans as a small boy. He pretends to have a skin condition, due to which he can't step into the sun. After killing Kyojuro, Akaza reports to Muzan and tells him of his victory. But he isn't pleased by the death of the pillar, but instead shows anger that Akaza let all the other present Demon Slayers get away.
In the Red Light District, Muzan talks to Daki. He tells her how proud he is of her and he hopes, she could become even crueler and stronger. He also lets her know about Nezuko and leaves it to her to kill her. After the fight, he gathers the Upper Moons to meet in the Dimensional Infinity Fortress. He is standing on the ceiling and experimenting, trying to heal his sun weakness. Muzan tells them that he won't allow any failures such as Daki and Gyutaro. Muzan regrets putting so much confidence in her and wishes Gyutaro had fought since the beginning. He tells them to serve him with more suicidal devotion and states how he hates change. He believes change only means decline and he didn't change for so long, since he is practically perfect.Hantengu that Nezuko was able to overcome the sun and is amazed by this. He is currently in the disguise of a small boy, when he hears of this. His foster mom and maid come in but Muzan instantly kills them. He is extremely excited and sets his mind on getting Nezuko.
He appoints Nakime the title of Upper Moon Four and makes her more powerful. He uses her to scout out the whereabouts of all Demon Slayers. He is quite impressed by her efforts and compliments her. He is sure to soon find Nezuko, who he thinks is actually an Ubuyashiki.
Muzan appears at the Ubuyashiki mansion and sees Kagaya. He mocks him for his weak appearance. Kagaya tries to lecture Muzan and points out how the Pillars will never give up, trying to kill him. Muzan laughed and then proceeded to kill Kagaya. But before that, the mansion was detonated, leaving Muzan behind weak and unable to regenerate quickly. Then Tamayo appeared and used spikes to keep him in place. All of the Pillars attacked Muzan at once, but he saved himself by teleporting all of them to the Dimensional Infinity Fortress and scattered them. He was certain they would now die.
Abilities and Powers
- Regeneration: Muzan probably possesses the fastest and most powerful regenerative power out of all Demons. This is seen when he instantly regenerated his body after being caught in the explosion of Kagaya Ubuyashiki and managed to circumvent the metal spikes added into the explosion. Additionally, Muzan has successfully overcome one of the Demons' prime weaknesses of being decapitated by a Nichirin Blade as seen when he easily regrew his destroyed head after it was completely destroyed by Gyomei Himejima.
- Extrasensory Perception: Muzan can feel the presences of both Demons and humans, including their bloodlust.
- Absorption: He has also displayed the ability absorb and assimilate biological beings and objects, as seen when he planned to absorb the flesh seed spike branches pierced into his skin and is now currently absorbing Tamayo a Demon, as well as planning to eat and assimilate Nezuko to obtain her immunity to the sun. He adapted to become immune to being beheaded by blades created with sunlight imbued metal. He also should be capable of adapting to poisons better than other Upper Demon Moons, who became resistant to wisteria poison which kills normal demons in seconds, and was able to adapt himself to a drug specifically made to transform demons back into humans.
- Immortality: Since he took Blue Spider Lily medicine, he can live many centuries without aging, and gains immunity to many diseases.
- Durability: At least superior to Tanjiro. He was hit by an explosion that reduced a house to mostly ashes , but remains mostly intact.
- Shapeshifting: Muzan can control his body's shape and even his presence, making him able to transform into someone completely different without even those with extrasensory perception noticing, though he cannot fool Tanjiro Kamado's smell. This shapeshifting allows him to become a child, and adult, a woman, or even to grow a pillar of flesh, eyes, and mouths to eat others, or a cocoon of flesh to dilate and adapt to poisons.
- Demon Blood Empowerment: As the first demon and creator of the demon race, Muzan's blood possesses powerful transformative qualities that once ingested by a normal human causes their bodies to immediately transform, giving them access to powerful regenerative abilities, enhanced strength, speed, reflexes and even gives them access to unique supernatural abilities called Blood Demon Arts. Muzan can also further empower a demon by giving him more of his blood further enhancing their preexisting abilities and giving them new powers altogether. However this ability is limited to how much blood the recipient can withstand and "adapt" to. If a human were to take in too much blood from Muzan, their bodies would mutate faster than they can withstand and it eventually causes them to self destruct into one giant mesh of flesh before disintegrating into ash. The same would also presumably happen to a demon if they couldn't withstand the blood's effects, as implied by Muzan.
- Telepathic Communication: Muzan has the ability to read the thoughts of demons that he has shared his blood with in close physical proximity to himself as seen when he read the minds of all the Lower Moons when he had them all gathered before him. Later it was displayed that he could also send telepathic messages and have full conversation with other demons as well, as seen when he was giving orders and checking on the statues on Upper Moon One, Kokushibo on how many Pillars he has defeated and to keep the Pillars at bay until he finishes recovering from Tamayo's poison.
- Curse: Muzan possesses the ability to put a curse onto the demon he creates by sharing his blood. If any demon he created even utters or says his name out loud the curse activates and destroys them, regardless of their original intent. This was seen with Susamaru who had accidentally said his name despite having no malice or ill intent towards him and was still destroyed by the curse implying that the curse automatically activates upon his name being said, because of this many demons simply think of him as "that Man" when needed to speak out loud regarding him. However, it has been proven that someone with sufficient will power can break free from the curse as seen with Tamayo and Nezuko Kamado.
Blood Demon Technique (
血 鬼 術 Kekkijutsu?)
- Black Blood: Spine of Thorns (
黒血・ 枳 棘Kokketsu: Kikyoku?): Muzan uses his own flesh and blood to create several spiked-barbed wires to entangle his target.
- Sunlight: Muzan is noted as the only demon to be immune to being killed via decapitation as seen when Gyomei destroyed his head and he still managed to regenerate and regrow it. Thus the only other method that he can be destroyed is through sunlight and is further given credence by his attempt of locating and devouring Nezuko in order to gain her immunity to sunlight.
- His first name, Muzan, means miserable and it also means atrocity, cruelty, cold-bloodedness, tragic, pitiful, and merciless.
- His last name Kibutsuji means "Demon Dance".
- He was made a demon in the Heian Period in the late 700's.
- Muzan was ranked in 11th place as of the first character popularity poll for the series with 285 votes.
- Due to his curly hair and white fedora during his debut appearance, many fans joke about Muzan physically resembling Michael Jackson, especially in Jackson's Smooth Criminal music video.
- "Do you have something you want from me? You're in quite a panic.."
- "I am a perfect creature that is infinitely close to perfection.
- "Does my complexion look terrible to you? Does my face look pale to you? Do I look weak to you? Does it look like I haven't got long to live? Does it look like I'm close to death?"
- "I want you to remove the head of that demon hunter with the hanafuda earrings." 
- "I now imagined that it would be better for the Twelve Demon Moons to consists of Upper Moons." 
- "It's only natural for demons to defeat Humans." 
- "But over here, anyone who lacks the power of a Pillar pretty much can't tell the difference, because we look like humans." 
- "There is a demon who escaped my control, just like Tamayo. Find her and put an end to her. You are the only one I can ask." 
- "The Ubuyashiki family has yet to be entombed."