5 Demon Slayer characters who were justified in becoming villains (& 5 who never should have)

Twelve Kizuki as seen in anime
Twelve Kizuki as seen in anime (Image credit: Ufotable)

Demon Slayer: Kimetsu no Yaiba is famous for its emotional storytelling that makes the audience empathize with almost all the Demon Slayer characters. They cleverly do this by showing it through the lens of Tanjiro Kamado, the protagonist. Many demons were once humans, who had to give up their humanity because they faced unimaginable pain, loss, or manipulation.

The characters of Demon Slayer just wanted to embrace evil and live upto their potential as the antagonist. Here's a look at five Demon Slayer characters whose villainy felt justified, and five who should never have turned to the dark side.


5 Demon Slayer characters who were justified in becoming villains

1) Akaza

Akaza, one of the Demon Slayer characters, as seen in anime (Image credit: Studio Ufotable)
Akaza, one of the Demon Slayer characters, as seen in anime (Image credit: Studio Ufotable)

Before he transformed into a demon, his human name was Hakuji. His past is perhaps one of the most emotionally complex stories in Demon Slayer. Hakuji was one of the Demon Slayer characters born into poverty, and he spent his childhood as a petty thief to take care of his father. Out of shame, his father committed suicide, and eventually Hakuji was banished from his hometown. With nowhere to go, he became an enraged teenager who found his redemption with a kind martial arts master who gave him another chance. Later, he fell in love with the man’s daughter, Koyuki.

When his fiancée and his master were poisoned by the rival Dojo, an enraged Hakuji went on a vengeful spree. Muzan took advantage of the situation and manipulated him to give up his humanity and turn into a demon. On transforming, Hakuji was given the name of Akaza. He never got an opportunity to grieve, and every time there was hope to lead a better life, someone stole it from him. Therefore, even if it was a misguided effort by Muzan, it is justified that he was one of the Demon Slayer characters who became a villain.


2) Rui

Rui as seen in anime (Image credit: Ufotable)
Rui as seen in anime (Image credit: Ufotable)

Rui was the Lower Moon Five demon. As a human, Rui was born physically frail and ill. Due to his condition, he had to be isolated and he was forced to maintain a distance from others. There was no hope for him to live a normal life, like playing with other kids or even making friends. When Muzan noticed him and turned him into a demon, it was like a gift for Rui. This was a chance for him to finally have enough strength to live a life that he wanted to. However, when his parents came to know about his transformations, they were horrified, and took the difficult decision to kill him and themselves.

Rui’s parents wanted to save his soul from being tainted by evil. In a moment when he was contending with the fear of losing everything and the newfound chance to live, Rui, plagued with rage, chose to kill them. However, the aftermath of killing his parents left him emotionally wounded till the end of his life. Therefore, after becoming a demon, Rui wanted to play family. He took up the role of a son and abducted other demons and forced them to play the role of his family members. His actions seemed cruel and childlike at the same time. Finally, Rui, as a Demon Slayer character, just needed love and connection. His methods were cruel, but villainy is tragic and entirely justified.


3) Gyutaro

Gyutaro before turning into a demon as seen in anime (Image credit: Ufotable)
Gyutaro before turning into a demon as seen in anime (Image credit: Ufotable)

Gyutaro’s life is devastating compared to the other Demon Slayer characters. Born in the Entertainment District, Gyutaro lived a life of squalor and abuse. He was constantly bullied by others, neglected, and, to survive, he needed to constantly fight for scraps of food. His reason and will to live was his younger sister Ume (later Daki), whom he raised and protected with fierce devotion. Their bond was strong and also the only reason he wanted to maintain his humanity and live for another day. However, he lost everything one day because of a cruel twist in his life. Ume was burned alive by a samurai, and Gyutaro was mortally wounded while trying to avenge her.

They were left to die on the streets, and no one batted an eye or tried to save them. This unfortunate event almost ended their lives, but they were given the opportunity to survive and become monsters. The transformation was the only chance they had to survive. As Upper Rank Six, they fought together, protecting each other with every ounce of strength they had. Their brutality stemmed from a life where kindness was never shown to them.


4) Tamayo

Tamayo releasing her Magical Aroma of Daylight, as seen in anime (Image credit: Ufotable)
Tamayo releasing her Magical Aroma of Daylight, as seen in anime (Image credit: Ufotable)

Tamayo is one of the most unique Demon Slayer characters. Her transformation to becoming a demon was not a decision she made. Muzan forced it on her, and, after she turned into a demon, she lost control and killed her family. It shattered her emotionally and mentally. Tamayo decided to live a life of redemption and dedicated her time to research on medicine and find a cure to reverse demonhood. Eventually, she partnered with Tanjiro and the Demon Slayer Corps to bring Muzan down. For the final battle, Tamayo managed to come up with a type of poison that would severely weaken him.

While she did technically become a demon, her villainy was brief and unintentional, and her actions afterward show her deep remorse and humanity. Tamayo’s transformation was justified because she became an important key in finding the cure to save Nezuko and Tanjiro. She’s a powerful symbol of what it means to reclaim humanity, even in the darkest of circumstances.


5) Enmu

Enmu laughing as seen in anime (Image credit: Ufotable)
Enmu laughing as seen in anime (Image credit: Ufotable)

Enmu was the Lower Moon One demon, and, if compared with other villain Demon Slayer characters, his life was not very tragic. Before becoming a demon, he was a doctor who took a deep interest in dreams and human emotions. It was this obsession that turned unhinged as his fascination with the concept of life and death grew. His bizarre mindset caught Muzan’s attention, and when offered to turn into a demon, Enmu embraced the opportunity.

His villainy is not rooted in cruelty or violence, it is rather directed towards his need to study human emotion in its rawest form. While he is still very dangerous, his fall toward villainy is understandable. Somewhere, he is a victim of his obsession rather than a monster by design.


5 Demon Slayer characters who were not justified in becoming villains

1) Muzan Kibutsuji

Muzan Kibutsuji as seen in the anime (Image credit: Ufotable)
Muzan Kibutsuji as seen in the anime (Image credit: Ufotable)

Muzan is the root cause of evil in this story. Every Demon Slayer character's life was twisted due to their need to seek immortality, but he represents pure narcissism and control. Unlike other demons, Muzan just wants to cheat death. As a terminally ill man during Japan’s Heian era, he underwent an experimental treatment that somehow gave him demonic powers. At this point, he started spreading his curse across the world. There was no need for him to actively transform other humans into demons, it was his choice to do so. He never wanted redemption and was blinded by power and greed.

Eventually, Muzan turned into a tyrant who treated his creations like pawns. He had no sign of affection or attachment even to his most loyal Upper Moons. His turning into a demon is not justified because if he hadn’t been so greedy, no one would have suffered any longer than they had to or lost their humanity.


2) Hantengu

Hantengu as a human in the Demon Slayer anime (Image credit: Ufotable)
Hantengu as a human in the Demon Slayer anime (Image credit: Ufotable)

Hantengu is one of the most infuriating Demon Slayer characters in the series. As Upper Rank Four, he is a vicious character who prefers to have a self-victimizing mentality, who never wants to be accountable for his actions. Even as a human, he was evil. Hantengu committed fraud, theft, and murder, and always thought he was innocent. Transforming into a demon was just more enabling for him to continue this way of life. He kept on killing innocent civilians, and wept because he claimed he was bullied. Moreover, he was delusional and always felt entitled.

Unlike other Demon Slayer characters like Akaza or Gyutaro, he never suffered or was manipulated. His suffering was all in his mind because he never acknowledged that maybe he was in the wrong. Hantengu never should have become a villain because he had no excuse, no turning point, and no awareness. His evil was selfish and pathetic, a product of a twisted mind with no sense of remorse.


3) Kaigaku

Kaigaku as seen in the Demon Slayer manga (Image credit: Shueisha)
Kaigaku as seen in the Demon Slayer manga (Image credit: Shueisha)

Kaigaku, as one of the Demon Slayer characters, was everything that stood against the code of a Demon hunter. As a human, he had the opportunity to train under Stone Hashira, Gyomei Himejima, and Kaigaku was once a fellow swordsman alongside Zenitsu. Unlike all these Demon Slayer characters who did good, he chose to be power hungry and arrogant. When he encountered Kokushibo during a mission, he begged for his life and willingly gave up on his humanity to become a demon. All of this just to become stronger. This selfish decision led to many other good Demon Slayer characters losing their lives, and he also tarnished the reputation of his mentors.

His life as a demon was more of his arrogance and the need to be stronger. Kaigaku belittled Zenitsu as a means of self-validation. His transformation wasn’t out of desperation or emotional collapse — it was out of cowardice and greed. He threw his life as a human away in a second when there was an opportunity to gain power. His story as one of the Demon Slayer characters was not justifiable but also disgraceful.


4) Doma

Doma as seen in anime (Image credit: Ufotable)
Doma as seen in anime (Image credit: Ufotable)

Doma never had any empathy from a young age. Born with colorful eyes, his parents created a cult around him. He was emotionally detached, and he never understood why people cried or felt pain. For him, human suffering was meaningless. Doma did not even grieve after witnessing his father murder his mother, and then kill himself. Being parentless did not seem to affect him. This was a hint towards his sociopathic nature.

When Muzan turned him into a demon, he was one of the Demon Slayer characters to accept it calmly, out of sheer curiosity. As for him, it was a way to experience something new. As Upper Moon Two, Doma led a cult and continued being indifferent about everything and everyone. He should never have become a villain because he was already one in spirit, and becoming a demon just allowed him to let it all out.


5) Kokushibo

Kokushibo as seen in manga (Image credit: Shueisha)
Kokushibo as seen in manga (Image credit: Shueisha)

Kokushibo was one of the Demon Slayer characters who was driven by vanity, jealousy, and fear. He was the twin brother of Yoriichi Tsugikuni, the founder of the Sun Breathing Technique. As a human, he was a strong warrior, but just not as talented as his brother. Finally, when he failed to master the technique invented by his brother, it was the last straw. When Muzan offered him to transform, he gladly accepted it.

It was his envy that led him into villainy. Therefore, there is no amount of justification that would help his case. As Kokushibo, he retained his discipline and battle prowess but abandoned his humanity. There was no tragedy in his life that pushed him to make his decision, it was pure fear and ego. The consequence of his decision was catastrophic because many Demon hunters lost their lives. His brother was also betrayed by his blood. His actions were not only selfish but also cowardly in nature.


In conclusion, these Demon Slayer characters walked a thin line between what is right and wrong. Ultimately, by choosing darkness for any reason, they were forced to face the consequences of their choice. This nuanced depiction is what makes Demon Slayer so compelling — it never asks the audience to simply condemn or forgive, but to understand where they come from and have empathy. It was a clever way to depict that we as the audience tend to side with humanity because we can feel the emotions that these villains cannot.

Edited by Vinayak Chakravorty