Muzan Kibutsuji is the main antagonist of Demon Slayer. He is a Demon, being the first of his kind, who has lived for more than a thousand years, being as such, the one responsible for the origin of the other demons, responsible for having corrupted Michikatsu Tsukiguni and being the one who murdered Tanjirō’s family and Nezuko, turning the latter into a Demon, being the trigger for Tanjirō’s desire for revenge towards him. In this article, we will talk about one aspect of Muzan’s story: his death. Muzan’s death was an overly long and complex process, which is why we are going to explain it to you.
After being defeated by the Demon Slayer Corps, Muzan devised an infernal plan on how to survive – he would pump all of his remaining blood into Tanjirō, turn him into a Demon, and thus survive. And while he did manage to turn Tanjirō into a Demon known as Demon King Tanjirō, his plan ultimately failed as Tanjirō managed to fight off his influence, thus killing Muzan once and for all.
The rest of this article will focus on Muzan Kibutsuji and his death in the Demon Slayer: Kimetsu no Yaiba series. Muzan Kibutsuji is a villain, but he is an exceptionally important character. His death was both a complex and intriguing process, so we have decided to dedicate this whole article to him and his death. This article will contain some spoilers from the Demon Slayer: Kimetsu no Yaiba manga, so be careful how you approach it.
Muzan was first killed by the Demon Slayer Corps
Originally from the Heian era, Muzan was a sickly young man whose transformation into a demon resulted from experimental therapy to extend his life. Before realizing he was at work, he killed his doctor. Since then, Muzan has dedicated himself to “finishing his therapy” by utilizing demons to help him accomplish his objective of being without flaws—the sun being his one weakness. Since he had a close call to death during his battle with Yoriichi Tsugikuni, he also voiced legitimate concern for individuals using the Sun Breathing technique.
Finding out that Nezuko and Tanjirō were threats to him, Muzan was actually fixated on finding them and eliminating them, but also copying from them their abilities, which would ultimately enable him to remove his own weaknesses and become, now completely immortal, as well as the most powerful being in existence. However, the Demon Slayers Corps took advantage of Muzan’s fixation on Tanjirō and Nezuko to capture him and eliminate his surviving supporters.
Before understanding that he was infected with a variant of the humanity-restoring serum that Tamayo and Shinobu produced with extra poisons that eliminated the majority of his skills and made him weak to be, Muzan manages to kill Tamayo and numerous Demon Slayers.
This was a truly epic fight. All of the active Hashira and the whole Demon Slayer Corps charged at Muzan simultaneously, a weakened Muzan. The goal was to fight him and keep him there until sunrise, which would cause the sunlight to completely eradicate him. And while the cost of that battle was high, as many Hashira and Demon Slayers, as we have said, died, Muzan was also on the brink of death.
The Corps managed to achieve their goal, and Muzan Kibutsuji was dying. Deformed and in a monstrous shape, Muzan Kibutsuji seemed to have been defeated, but this was not his true end. Namely, he did technically die at this moment, but he found a way to keep himself alive for a bit longer, and that was Demon King Tanjirō, whom we are going to tell you about in the next section.
Muzan was, then, killed off by Tanjirō. And for good.
Demon King Tanjirō is a name given to Tanjirō Kamado’s final Demonic form after he had been turned into a Demon by Muzan Kibutsuji. It was Muzan’s final attempt at destroying Tanjirō, but he was ultimately unsuccessful thanks to the efforts of Tanjirō’s sister, Nezuko Kamado, and Kanao. In this section, we will tell you all the narrative details concerning the character.
In reality, Muzan Kibutsuji’s passing catalyzed the events that turned Tanjirō into a Demon. Specifically, the Demon Slayers ultimately succeeded in destroying Muzan, albeit at a high cost. Muzan thought about his life and the meaning of immortality as he passed away and realized—with tears in his eyes, mind you—that he would never be able to achieve it.
Then it occurs to him that Tanjirō might be the one to carry out his scheme! Tanjirō would grow to be the most powerful Demon in history, would genuinely be immortal, and could execute Muzan’s plan as he had originally meant. Tanjirō would have immunity to sunlight like Nezuko and would be unkillable because he is the only one who knows the Sun Breathing technique.
Having realized that, Muzan Kibutsuji makes a final effort and pumps absolutely all of his remaining blood into Tanjirō Kamado, which turns him into the entity known as Demon King Tanjirō.
Tanjirō started battling the Demon Slayer Corps in his new demonic form. He first faces off against Inosuke Hashibara and Giyu Tomioka, who are unable to overcome him. As Tanjirō’s rebuilt body is further malformed by Muzan’s demonic blood, Nezuko pushes him to resist letting Muzan take control. He attacks Zenitsu, but Giyu intervenes to protect him. Soon later, Kanao shows up with the last humanization drug and walks over to Tanjirō to administer it.
Tanjirō converses with Muzan’s remnants in his thoughts as his body is engaged in combat with the Demon Slayer Corps. Muzan Kibutsuji implores Tanjirō to give him control so that Tanjirō might become the supreme being—the most powerful, eternal, and unbreakable being—but Tanjirō rejects and fights Muzan’s influence fiercely from within. At one point, Tanjirō acknowledges the attempts to reach out to him made by the hands of his friends, family, and loved ones inside of his thoughts.
Tanjirō is then brought back to reality. As his demon form disappears, we realize that Muzan Kibutsuji is finally dead. Nothing remains of the former demon lord, and with him, Demon King Tanjirō also disappears, and the saga is finally over.
Muzan’s last words were a cry for help
As he was dying within Tanjirō, Muzan uttered these final words: “Tanjirō! Tanjirō, don’t go! Don’t leave me here!” This was the last we saw of Muzan. Not long after that, a recovered Tanjirō woke up among his friends, as the last remaining traces of Muzan and his consciousness withered away. This proves how miserable Muzan was, how helpless of a character he was, and how all of his demonic acts and murders were just a cry for help.
Deep inside, Muzan was alone and miserable; it was, of course, the result of equally tragic consequences (as he was not turned into a Demon because he wanted to be one), but Muzan never really fought this. He simply accepted it and became evil, wanting to take revenge on the world that, from his perspective, had seemingly forsaken him. This is why his last words were befitting of his overall story in the series.
When Muzan died, all of the demons died as well
Now that you know everything about Muzan Kibutsuji’s death in Demon Slayer, you must be wondering what happened to the other demons in the series? Well, we actually have an answer for you in that aspect. Namely, the Demon Slayer Corps did not eliminate all the demons; Muzan and the Twelve Kizuki were dead, but there were many other demons in the world that the Corps had not found by then, and they were still free. So, what happened to them?
Well, as the series undoubtedly confirmed, all the Demons that were created from Muzan’s blood (either directly or via a proxy) died along with Muzan. With Muzan dead, his blood also died out and the demons simply died, as you’d expect. Otherwise, the Corps would not have been disbanded and the Demon Slayers would continue hunting for demons; plus, it would bring to a potentially endless cycle of fighting, as the surviving demons could turn others into demons as well and the whole story would simply continue, only without Muzan. And since the author wanted peace in the end, he had all the other demons die.
Now, you might ask yourselves – but what about Yushiro and Chachamaru? They’re demons but they survived, right? Yes, they did, and it is a fact that the post-Muzan era was not completely demon-free as the author said; no evil demons were present, but two demons actually survived. So, how was this possible? Easy – they did not have Muzan’s blood in them!
As you know, Yushiro was turned into a demon by Tamayo to save him from death and without even a drop of Muzan’s blood, so he was not tied to Muzan in any way. She did the same to Chachamaru, although not many details were provided. Be that as it may, all the demons died save for these two, who survived because they were not related to Muzan in any way.