Why Did Dōma Become a Demon & How Is He Able to Turn Other Humans into Demons?

The Demons of Demon Slayer are a truly fascinating lot. They come in all shapes and sizes, and while they are evil in their demonic form, their backstories and their lives while they were human usually contain a very tragic note that makes you feel sad for them. But there are also exceptions, and one such exception is the protagonist of this article – Doma. The Upper Rank Two of the Twelve Kizuki, Doma is an exceptionally powerful Demon and a very vile character at that. In this article, you are going to find out why Doma became a Demon in the story and how was he able to turn other people into Demons as well.

Doma was turned into a Demon by Muzan when he was 20 years old; he admired Muzan for his power and since he was a vile person, he probably just wanted more power for himself, which would make sense from his perspective. Due to the fact that he actually received a very large amount of Muzan’s blood, the only thing that can turn a human into a Demon, he was able to turn other people into Demons as well.

The remainder of this article will give you a detailed overview of Doma’s story, as it happened on the pages of the Demon Slayer: Kimetsu no Yaiba manga. You already know what happened and how it happened, so we will just bring you the details so you know the whole context. Be careful, though, as the article will contain many spoilers, so if you don’t know all the details, be careful how you approach the text.

Doma became a Demon because he admired Muzan

Doma is introduced to the story as an exceptionally powerful demon and a member of Muzan’s Twelve Kizuki, where he holds the rank of the Upper-Rank Two, meaning that he is the second most powerful demon in the group; the first one is Kokushibo, Yoriichi’s brother. Due to his beautiful rainbow eyes and pure white hair, Doma was considered a supernatural being from birth and became the religious leader of the Heavenly Faith Cult, a position he maintained until nowadays.

While Doma was still a child, his mother had a complete psychotic breakdown. She attacked his father, stabbing him to death in the process because he had numerous extramarital affairs with other female members of the cult they belonged to. She poisoned herself to death right away and committed suicide. Even though he directly witnessed the sadistic revenge murder, which played out right before his eyes, Doma was merely annoyed by the blood and the mess left behind and revolted by the overpowering smell of blood.

He merely wished to ventilate the space before the smell solidified on the furniture. He encounters Muzan Kibutsuji when he is 20 years old, who turns him into a Demon. Because he consumed so much of Muzan’s blood as part of the transformation, Doma became an exceptionally powerful Demon.

The exact reason for this was never actually revealed. We know that Doma has admired Muzan his whole life and that he was also a very vile and narcissistic person who wanted even more power than he had. Meeting Muzan, he probably “fell in love” with his authority and simply wanted to be like him, which is why he accepted his proposition. This could also be the reason why he took so much of Muzan’s blood, a feat that could’ve killed him (Muzan’s blood is extremely potent, and even small amounts of it could kill a person if they were not strong enough to bear it), and became so powerful.

He admired Muzan, and as Muzan promised him more power, he gladly accepted. As we have said, this was not officially confirmed in the series, but based on what we know about Doma and his personality, it could very well be the reason.

Muzan’s blood enabled Doma to create other Demons

The only way to transform a human into a Demon, aside from the original method with the Blue Spider Lily, is for them to consume and survive the consumption of Muzan’s blood. This means that only Muzan and those who have a large enough quantity of Muzan’s blood can transform other people into Demons. Such Demons are, of course, the most powerful ones, which means that only the Upper Moons, and not even all of them, as far as we’ve come to understand, are able to do so.

As far as it has been confirmed, Akaza, Doma, and – of course, Kokushibo are able to do it, aside from Muzan. Akaza offered Rengoku to transform him into a Demon, Doma turned Gyūtarō and Ume into Demons, and Kokushibo offered Muichiro to turn him into a Demon when they fought. All three of them had exceptionally high amounts of Muzan’s blood in them, allowing them to transform people into Demons.

As for Doma, he is notably known, as we’ve said, for having turned Gyūtarō and his sister Ume into Demons. They would later become the Upper-Rank Six, known as Gyūtarō and Daki. Gyūtarō was born into poverty in the lowest class of the red-light district. His mother often beat him and tried to kill him because she could not afford to support him. Throughout his childhood, he was continually mocked for his appearance by the other residents of the neighborhood. When his sister Ume was born, he acquired a sense of pride and responsibility, probably also due to his mother’s mental instability and her subsequent death, which led him to raise her until her early teenage years.

Ume, as a human, was an honest, naïve young girl whose singular beauty—including blue eyes—caught the eye of numerous men. This is the reason why Gyūtarō was so protective of her. When she was 13, she blinded a samurai with her hairpin, and she was, in the act of revenge, tied, burned to near death, and left in a ditch in the Entertainment District, where Gyūtarō. Gyūtarō wanted revenge but was soon struck in the back by that same samurai. After finding out that the brothel manager wanted him dead, he killed her and the samurai and fled with his sister. The two of them nearly died, but Doma, who was looking to devour some girls in the area, found them and – because he was such a “nice guy” – he offered to turn them into Demons, which they accepted.

He then challenged them to become more powerful, and they eventually did, becoming the Upper-Rank Six, before being killed by the Demon Slayers.