For those who have watched only the first season of the anime, they will be surprised to know that Muzan turns into a woman in the second season.
Muzan is a tall and muscular man, with an unnaturally pale skin complexion that can be easily confused as being unhealthy and sickly. He has curly black hair, and sharp, almond-shaped eyes.
He does this to confuse the demon slayers/hashiras. This changes his aura as well, so they won't be able to recognise him by scent or anything else.
Technically, the elder of the two Sakuras` was actually Muzan`s child, by way of his mistress (Lady Jade Wong), who had one of her eggs inserted into Anne`s body.
Muzan Kibutsuji (鬼舞辻無慘, Kibutsuji Muzan) is the main antagonist of the Demon Slayer: Kimetsu no Yaiba fantasy action manga and anime series. Muzan is the powerful King of all the Demons, who has the ability to inject his victims with blood that allows him to convert them into more Demons.
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.
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 is shown to have a positive master-servant relationship with Daki, as the young Demoness seemingly worships and admires the Demon Progenitor immensely, fervently hanging on each and every one one of his words and doing her absolute best to accomplish the tasks he gives her.
Yet an official Demon Slayer "fanbook," written by the manga's creator, Koyoharu Gotouge, revealed Muzan doesn't really like Upper Rank Two demon, Doma. As Lower Ranks Six, Four, Three and Two can attest, Muzan is not averse to eliminating demons he doesn't care for, even if they're Kizuki.
When Demon Slayer's Tanjiro met Muzan in Tokyo, Muzan had a human wife and daughter with him. There's a chance he genuinely cared for them. In the story of Demon Slayer, demons are supernatural creatures of the night who consume human flesh to survive.
Later it is revealed that he married fellow slayer Kanao Tsuyuri. In the Modern World, Tanjiro and Kanao had descendants named Sumihiko Kamado and Kanata Kamado.
Muzan has had more than one family over the course of his millenia-long life. This includes the birth family he had before he became a demon. In addition to them, Muzan took five wives.
Muzan is born into what would be the future Ubuyashiki Clan, likely in the Heian capital (modern day Kyoto). Assumed stillborn, he is barely rescued from cremation (a sign of being born very high class nobility).
Demons cannot have offspring (if they do have kids and descendants it was before they became a demon, the child is most likely not Muzan child.
They've always existed as villains, notably with people like Starscream in Transformers. The difference here is that Muzan is the big bad, someone who's meant to be the alpha and omega in the series. Your top tier villain is rarely cowardly. It's what makes Muzan so interesting as a character.
Muzan is another Pure Evil villain from Toshihiko Seki along with Lord Embryo.
Curse of Kibutsuji
This curse besotted any who partake of Muzan's blood must be careful. The curse prevents Muzan's name from being spoken aloud, and any who do will meet a horrible demise.
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. Yoriichi encountered Muzan and Tamayo in a bamboo forest, where the two engaged in combat.
So the only reason Muzan is afraid of Tanjiro is because of the Hanafuda earrings he possesses, which acted as a reminder of his downfall. nxt. Hanafuda Earrings are a symbol of Sun Breathing users, traditionally passed down from generation to generation as a family heirloom.
While it is not explained in the anime why he did so, Muzan is shown to be living a normal life as a human. Not only that, he's married a woman and has a child with her.
Thus, Muzan created demons for hundreds of years even when he didn't want to turn someone. 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.
She Is Over 100 Years Old
Even though Daki has a youthful appearance, she is actually over 100 years old. Many of Muzan's demons look young, but it is especially surprising to learn that Daki is one of the oldest demons.
Yoriichi was powerful enough to defeat Muzan; however, he couldn't do so. That's because he couldn't come down to kill his twin brother, leading to his own demise. Even to this day, Muzan is scared of Yoriichi.