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MangaDemon Slayer Characters and demons Who Is Muzan Kibutsuji? Why He Became a Demon 1,000 Years Ago and Why He Hunted the Blue Spider Lily
Muzan Kibutsuji was a young aristocrat in the Heian period, over a thousand years ago, who was dying of illness. A doctor's medicine saved his life, but in exchange he got a body that couldn't bear sunlight and had to eat people: he became the first demon. Believing the "blue spider lily" used in the medicine was the key to conquering the sun, he searched for it for a thousand years. The wounds Yoriichi Tsugikuni gave him in the Warring States period tormented him to the end. The Ubuyashiki family, who lead the Demon Slayer Corps, share his bloodline.
This article covers Demon Slayer up to its final chapter.
Who was Muzan originally?
A young aristocrat in the Heian period.
He was sickly from birth and wasn’t expected to live to twenty. A doctor made a medicine to extend his life. Impatient when it didn’t seem to work, Muzan killed the doctor. But afterward, his body became strong and he stopped dying.
In exchange, he could no longer go out in the sun, and he couldn’t stop himself from eating people. That was the beginning of the first demon.
Why did the blue spider lily matter?
Because Muzan believed it was the key to conquering sunlight.
The doctor’s medicine is said to have used a blue spider lily. Muzan believed that if he found the flower, he could have a perfect body that could live in the sun, and for a thousand years he had his demons search for it.
He never found it. Instead, the one who conquered the sun was Nezuko. That’s why Muzan starts hunting her.
Who did Muzan fear?
Yoriichi Tsugikuni, a swordsman of the Warring States period.
Yoriichi used Sun Breathing, the origin of all Breathing styles. Cornered by Yoriichi, Muzan escaped only by bursting his body into pieces. The wounds he took that day kept burning inside him for centuries. His drive to wipe out every swordsman who used Sun Breathing came from his fear of Yoriichi. Yoriichi is covered in the Kokushibo article.
What’s his link to the Ubuyashiki family?
They share his bloodline.
The Ubuyashiki family, who lead the Demon Slayer Corps, came from the same clan as Muzan. Because the clan produced a demon, the story says, the Ubuyashiki men have been sickly for generations, cursed not to live past thirty. Leading the Corps for a thousand years was also their way of atoning. More in the Kagaya Ubuyashiki article.
What did Muzan feel at the end?
In his final moments, Muzan is shown realizing how strong it is for people to pass their will on to others. Having only ever wanted his own life to last forever, at the end he tries to pass his will on to Tanjiro.
Personally, I think this is the greatest irony of Muzan. A demon who spent a thousand years afraid of death tries, at the very end, to copy what humans had always done: entrust something to someone else. But by then it was too late.