The anime Demon Slayer, based on Koyoharu Gotouge’s hit manga of the same name, follows the story of Tanjiro Kamado as he trains to become a Demon Slayer and track down Muzan Kibutsuji. As the first of his kind, Muzan is the main antagonist of the story and is known as the Demon King. Muzan became Tanjiro’s enemy after he killed Tanjiro’s family and turned his sister, Nezuko, into a demon.
Throughout his journey, Tanjiro meets many demons. Most of these demons are under a curse and must work for Muzan Kibutsuji; very few have the strength to break free. With different influences in each demon’s life, they all have different stories. Which demons have interesting backgrounds that make them intriguing to viewers -- and which ones aren’t worth the time?
Nezuko, Tamayo and Yashiro
Nezuko Kamado is the younger sister of Tanjiro Kamado and the only other survivor of Muzan Kibutsuji’s attack on their family. However, Nezuko suffered the unfortunate fate of being transformed into a demon by the Demon King. As a demon, Nezuko’s journey starts off like any other -- bloodthirsty and unable to fight off demon instincts. It isn’t until her brother protects her from Giyuu Tomioka, a highly skilled Demon Slayer, that she is able to combat the curse that Muzan put on her. After this, Nezuko becomes protective of Tanjiro and joins the fight against those demons under Muzan’s control. Nezuko’s story is incredibly important for many reasons. Not only is her transformation a pivotal plot point, but through flashbacks and choices she must fight strongly to make, viewers learn about the difficulties that demons go through as their actions go against their morals.
Tamayo and Yushiro are the first demons that Tanjiro and Nezuko meet who are able to fend off being under Muzan’s control. The two meet Tanjiro and Nezuko after Tanjiro’s first encounter with Muzan. Tamayo is a skilled doctor and Yushiro works as her companion, assisting her when she needs his help. Tanjiro, Nezuko, Tamayo and Yushiro work together to fight off demons that Muzan sends to attack the siblings. Their teamwork pays off through trust and abandoning fear. Tamayo sympathizes with Tanjiro, and they agree to work together to come up with a cure for those who have fallen victim to Muzan’s curse. The story of these two demons shows that there are more demons than just Nezuko who have the strength to fight Muzan and are willing to step up and help Tanjiro through his mission.
Rui, Gyutaro and Daki
Rui is physically presented through the body of a young boy but has been around long enough to travel up the ranks and become a member of the Twelve Kizuki, the 12 most powerful demons who answer directly to Muzan. He is the first of the Twelve Kizuki that Tanjiro encounters, and he works with many other Demon Slayers to kill Rui and his demon family. Rui’s backstory reveals his desperation for connections with other demons and his jealousy over the bond that Tanjiro and Nezuko have.
As a human, Rui was quite ill but was given the chance of immortality by Muzan. Rui’s parents realized that their son had been turned into a monster and attempted to end his life, followed by their own. In an attempt to save himself, Rui killed his parents with no remorse, only focusing on the fact that they were planning to kill him. It wasn’t until Rui’s demon life was over that he realized the love his parents had for him. His desire for familial love and connection is only truly met after he is freed from Muzan’s curse and reunited with his family in the afterlife.
Gyutaro and Daki serve as the Upper Rank 6 demon in the Twelve Kizuki. They were once young children who lived in an impoverished area and had to do whatever it took to survive. As a human, Daki was considered quite beautiful and started working at a brothel. Gyutaro was seen as quite the opposite, bullied by children and adults alike for how he looked. After a customer of hers insulted her brother’s appearance, Daki went into a fit of rage and stabbed the man in the eye. This man, along with Daki’s manager, attempted to kill the siblings, but Gyutaro won the battle. After they were extremely weakened, the two met a member of the Twelve Kizuki who offered to help them become demons. Their bond can be compared to Tanjiro and Nezuko’s, and it shows a different chance of what can become of two people when the world is nothing but cruel to them.
Kyogai and the Swamp Demon
Kyogai is one of the first demons that Tanjiro has the chance of fighting with the help of his new friends Zenitsu Agatsuma and Inosuke Hashibira. This demon was once a member of the Twelve Kizuki but was later removed from the ranks due to his lack of strength. During the "Mansion" arc, where Kyogai plays the main antagonist, viewers learn that Kyogai never felt good enough, even as a human. He was beaten down for his lackluster work as a writer and as a demon. While Kyogai’s abilities are interesting, his story isn’t impactful toward the main plot line at all. The only things that make his plot worth watching are the other characters and the battles that occur. However, the reflection on Kyogai’s life interrupts what is most enjoyable about this arc.
The Swamp Demon plays the main antagonist during Tanjiro’s very first mission as a member of the Demon Slayer corps. Tanjiro must find where teen girls from a village are going after they end up missing. It is discovered that a demon is able to travel through a swamp domain of his own creation. He is able to travel through surfaces to appear in different areas in the real world and take things back with him. The Swamp Demon is also able to split himself into three bodies, each acting drastically different as he splits strong personality traits into each version. There isn’t much to learn about the Swamp Demon’s backstory, as little is provided, which is why his character is so disappointing. As a very strong demon with fascinating powers, his lack of a story ends up in an arc that feels like it’s missing something.
As a story that focuses on the execution of demons, there are many characters that fans meet. This journey provides wonderful backstories to some very interesting demons, but not all of their stories are worth the time that's spent on them, while some demons’ lives deserve to be looked into more. However, in the end, every demon is responsible for helping Tanjiro and Nezuko grow as they fight to end Muzan’s curse.