The Anti-
Additionally, Muzan instinctively realized that he would die if he were ever to be exposed to sunlight. Whatever medicine the physician had crafted using the Blue Spider Lily had effectively granted Muzan immortality, transforming him into the world's first demon.
History. Muzan was born in Japan's Heian era, to a constant struggle to survive on account of his frailty. His heart stopped multiple times in his mother's womb, and when he first entered the world, he was deemed stillborn, having no pulse and not breathing.
Tamayo failed to kill Muzan by poisoning him, thus he came back to life. Tanjirou and Giyuu are the first one to approach him. There they fight Muzan Together without stopping. They realized that the only way to kill Muzan is to drag him into the sun.
After he neutralizes Tamayo's poison and emerges from his flesh cocoon, Muzan's hair grows in length and turns white due to Shinobu's poison accelerating his age. He also grows numerous mouths all over his limbs, each one lined with a set of incredibly sharp fangs.
Abilities. Demon Body: Unique from other demons, he possesses seven hearts, and five brains. These are responsible for his powerful vitality, should any of them be harmed, he will be severely weakened.
Muzan's Blood Demon Art is known as “Biokinesis.” It allows him to alter his body and shapeshift at will. Although all demons have this innate ability, Muzan elevates it by modifying his flesh and organs. Biokinesis is also the only reason Muzan has been able to hide from the Demon Slayer Corps for 1000 years.
Don't go! DON'T LEAVE ME HERE! Muzan speaks his final words as he loses control over Tanjiro.
Thanks to Somiyoshi, and later on Tanjuro who passed it down to Tanjiro, the world is left with a weapon to defeat Muzan Kibutsuji, long after Yoriichi passed away. Those are ultimately the role of Tanjiro's father, Tanjuro Kamado, in the story of the Demon Slayer.
Muzan Kibutsuji has done some terrible things in Demon Slayer, but his slaughter of Tanjiro's family is one of the most mysterious.
It is revealed that Muzan's true fear of dying and immense desire to live and survive was due to him being born "dead," where his heart would constantly stop in his mother's womb and was assumed stillborn until he fought to breathe before his cremation.
Haruka Shiraishi: Muzan's Daughter.
Anne was originally planned to be Muzan`s older sister, who died by the hand of a Demon Slayer but that idea was scrapped, as the author knew practically nothing about Muzan`s early life. Instead, Anne became his wife, by which he had two children.
The Anti-Kibutsuji Drug is a special four-stage drug that was created by the combined efforts and medical expertise of Tamayo, Yushiro and Shinobu Kocho with the main purpose of annihilating, Muzan Kibutsuji.
Demon Slayer hints that consuming the Blue Spider Lily can negate a demon's vulnerability to the sun, which is why Muzan spent ages hunting for the bloom. As the strongest being in the world, Muzan's only weakness is the sun.
The warrior Muzan feared was a swordsman named Yoriichi Tsugikuni. Yoriichi was the only slayer before Tanjiro who came close to killing Muzan, and the flashback of their fight occurred in Chapter 187.
However, in the Demon Slayer manga Muzan reveals his motivation for attacking the Kamado family. It turns out that Muzan attacked the Kamado family and specifically turned Nezuko into a demon in an attempt to create a demon that would be able to withstand being in the sunlight.
As it turned out, the scar on Tanjiro's forehead did have some significance to it, rather than simply being a Todoroki-esque burn from scalding water. Tanjiro wasn't born with this scar on his forehead. Rather, he acquired it when tackling his younger brother out of the way of a falling pot of boiling tea.
Since he didn't know anything about the Blue Spider Lily medicine, he needed others to find the plant for him by happenstance. This is the general reason why Muzan turned Nezuko into a demon. More specifically though, was the fact that Nezuko was of Kamado blood.
Since Muzan favored Gyutaro so much, he chose to incorporate the latter's sister Daki as well. The demon king believed that she was the only tool that could be used to control Gyutaro.
Muzan's loyal wife and daughter seem like convenient test subjects to help him synthesize a cure for sunlight weakness as a backup in case the Blue Spider Lily is never found. The young girl might even be Muzan's biological child, a half-demon who gives off the scent of a human while having his essence in her.
Muzan's telepathic powers leave other demons' thoughts open to him just by catching sight of them. He can speak to them in their heads even when they are far from him. Although his range is somewhat limited, he can also locate them with this connection and feel what they feel.
Nezuko's Blood Demon Art is “Pyrokinesis,” which allows her to generate and manipulate special demonic flames created from her blood. It may be because of her unique nature, but her flames have a special ability, making them only harmful to demons and anything related to demons.
Ever since he became a demon, Muzan's goal has always been to become a “perfect being.” He wants to rid himself of all his weaknesses. However, the one thing he cannot defeat is the sun. All demons have a natural weakness to sunlight since they disintegrate when exposed to it.
The only Demon he despises the most is the Upper Rank Two: Doma. It is quite a shocker that the second most potent Demon in the Demon Slayer is not Muzan's favorite.