Muzan Kibutsuji is the main antagonist of the fantasy horror manga / anime series Kimetsu No Yaiba. He is the progenitor of demons, this being the first of his kind.
He is responsible for the death of Tanjiro Kamado's family and he was the one who turned his sister, Nezuko, into a demon.
Appearance[]
Generally, Muzan has the appearance of a pale man. One of his main abilities is to change his appearance. He normally appears as an attractive male human with a slick hairstyle and red eyes. His attire normally consists of a fedora hat, a black jacket, and long white pants.
Muzan's second form is that of a woman with her hair up wearing a kimono, while his third form is that of a boy of apparently about 12 years old.
Personality[]
Muzan is generally a ruthless, cold, intimidating, and fearsome individual. He lacks complete appreciation of others, including other demons like the members of the Twelve Kizuki whom he sees as mere pawns in his plans. Also, he is short tempered and intolerant, since he does not tolerate the failure of his henchmen and does not hesitate to kill them or give them severe punishments.
Despite all this, he has shown to be somewhat fearful, which is reflected in his fear of Tanjiro due to the fact that Hanafuda's earrings remind him of a Demon Hunter who was about to kill him, so he sends his lackeys to remove it. Still, he's smart, calculating, and meticulous. Due to his threatening and temperamental nature he is highly feared and respected by the other demons.
Story[]
Human Life and Origin as a Demon[]
Muzan was born in Japan during the Heian Period (over 1,000 years before the series) with a terminal illness that caused his heart to stop periodically. Fearing death, he became a test subject for a mysterious doctor who experimented with a prototype medicine called the Blue Spider Lily. After consuming it, Muzan gained immense strength and regenerative abilities — becoming the first demon — but still couldn’t walk in sunlight. Enraged at the doctor’s slow progress, Muzan killed him, not realizing that the cure was incomplete. The doctor had been close to creating a perfect balance, but with his death, the Blue Spider Lily was lost. Since then, Muzan has been obsessed with finding the flower or creating a demon capable of walking in sunlight, hoping to absorb them and become the perfect immortal being.
Muzan’s Manipulations Across History[]
Over the centuries, Muzan spread his blood to create countless demons, forming the Twelve Kizuki to act as his enforcers. He experimented with humans, demon evolution, and mutations to find one who could overcome the sun. He caused widespread terror throughout Japan and was behind countless tragedies.
He feared only one thing: the Breath of the Sun, the original breathing style developed by Yoriichi Tsugikuni, the only person who ever nearly killed him. Muzan narrowly escaped death after being sliced into over 1,800 pieces by Yoriichi, barely surviving by dispersing his cells and fleeing. This encounter scarred him for life and made him fear anyone with Hanafuda earrings or Sun Breathing.
During the Actual Story[]
In the opening chapter, Muzan kills Tanjiro Kamado’s entire family, turning Nezuko into a demon. This sets the story into motion. Muzan later denies recognizing Tanjiro but is disturbed by his earrings, which remind him of Yoriichi. He sent many demons to murder the Demon Slayer Corps and find the Blue Spider Lily, but many of them failed and got killed. However, he found out that Nezuko managed to resist the sunlight, which excited him and made him admit that any demon he used was useless.
Infinity Castle Arc (Final Confrontation)[]
After many of the Upper Ranks are killed, the Demon Slayers finally corner Muzan. Tamayo, a demon who rebelled against him, assists the Demon Slayer Corps by injecting Muzan with a potent anti-demon drug. During the battle in the Infinity Castle, Muzan reveals his true form and unleashes his full might.
The anti-demon drug slows Muzan down, aging him rapidly and suppressing his regeneration. Still, his power is overwhelming — he kills many and nearly wipes out the entire Corps. Tanjiro and his allies push themselves to the brink, stalling him until sunrise.
Powers and Abilities[]
Muzan is undoubtedly the most powerful demon of all as the Progenitor. He has proven to be an extremely difficult opponent to beat, as it took more than 5 Pillars to face him. He is the only demon that has the ability to transform humans into demons through his blood. Mainly, he has the ability to command fear and fear through his threatening presence and his indifferent and serious attitude, in order to receive respect and dominate those around him. Muzan possesses the ability to put a curse on the Demon that he creates by sharing his blood. If any Demons he created even speak his name out loud, the curse activates and destroys them, regardless of his original intention. This was seen with Susamaru, who accidentally said his name despite having no malice or bad intention towards him and was still destroyed by the curse, implying that the curse is automatic. Like all demons, Muzan has an extremely accelerated regeneration, allowing him to heal wounds in a few seconds whether they are superficial or deep.