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How did Muzan Kibutsuji become a demon in Demon Slayer?

Get ready anime fans, new Demon Slayer lore just dropped and its good. Here we explain how the villain Muzan Kibutsuji became a demon in the hit anime series.

How did Muzan Kibutsuji become a demon in Demon Slayer: a close up of Muzan in the Demon Slayer anime

How did Muzan Kibutsuji become a demon in Demon Slayer? Demon Slayer season 3 is packed with thrilling fights and overpowered demons but also a shocking amount of lore. One of the biggest revelations from the anime’s latest episodes was the backstory of Muzan Kibutsuji. Warning Spoilers ahead!

Muzan Kibutsuji is one of the toughest anime villains in existence, and to be honest, we doubt that Demon Slayer would be one of the best anime series around right now without him. Muzan is the father of all demons, using his blood to create unholy sinners and man-eating monsters. But have you ever wondered how this Demon Slayer character came to be? Was he the first demon? How did he turn into the immortal monster we all know today?

Well, The Digital Fix is here to answer all your burning questions down below. Here we fully explain how Muzan Kibutsuji became a demon in Demon Slayer and give you a breakdown of the anime character’s intriguing backstory.

How did Muzan Kibutsuji become a demon in Demon Slayer?

Muzan Kibutsuji became the first demon in Demon Slayer after ingesting medicine made from the Blue Spider lily flower that was mixed with the blood of his murdered doctor.

Basically, Muzan has always been afraid of dying, and unfortunately, back in his human days, he was terminally ill. His illness led to him hiring a doctor who would give him multiple remedies, but no known medicine could counter his weakening body. After becoming frustrated that none of the treatments were working, he eventually murdered his doctor.

But it turns out that Muzan was too hasty with his killing spree. The medicine that his doctor was working on not only cured him but, when mixed with blood, turned him into an immortal monster. But it wasn’t perfect.

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After taking the blood-soaked medicine, Muzan gained supernatural abilities, immortality, as well as an appetite for human flesh. However, the medicine also made it impossible for him to venture out during the day, as sunlight burned him.

Obviously, Muzan isn’t too happy about his sunlight restrictions since he isn’t truly immortal with such a major weakness. His obsession with surviving daylight led him to create more demons using his blood, hoping that one day a demon who could withstand the sun would appear so he could absorb their power for himself.

If you watched the Demon Slayer season 3 ending, you would know that Nezuko is now the first demon to officially survive sunlight, meaning that Muzan is now hell-bent on finding her and gaining her power by any means necessary. Exciting times!

Personally, we can’t wait to see how Muzan begins his search for Nezuko in Demon Slayer season 4! But while we wait, fans can now look over our guides to the best anime movies, and the best horror anime of all time, and everything we know about the Chainsaw Man season 2 release date.