Summary
The two main star characters ofDemon Slayerare the titular faction itself and their eternal enemies, the demons. It’s more than a classic case of good versus evil and sometimes borders on modernity versus tradition as it’s set during the start of the industrial age. Regardless, the Demon Slayer Corps always have their hands full with all the roaming demons around.
The anime has revealed almost every member of the Upper Rank Demon Moons, with some particularDemon Slayervillain namessending chills down a viewer’s spine. There’s no denying the fact that these heinous figures are so outright evil and remorseless that it’s easy to see how much of a menace they are to humanity’s progressing civilization. TheseevilDemon Slayercharactersare sure tomake Tanjiro and Nezuko’s livesa living hell as they strive to end the threat of these creatures of the night once and for all.
Updated on August 05, 2025, by Ritwik Mitra:Demon Slayer’s Hashira Training arc set the stage for one of the biggest battles in the final series that will set the stage for the battle between Muzan and the Upper Rank Demon Moons against the Demon Slayer Corps. Fans can’t wait to see some of the biggestDemon Slayer villain namesget their comeuppance as they face off against a retinue of talented demon slayers who must awaken their mark by any means necessary to fight on equal ground against these foes. Given the brutal nature of this world, it’s only a given that some characters in Demon Slayer are bound to be as evil as they come, performing horrifying acts that will turn them into easily hateable characters that deserve everything that is coming at them.
20Sanemi Shinazugawa
Most Evil Act: Almost Beheading Nezuko In Front Of Her Distraught Brother
Sanemi may not be aDemon Slayervillain name, but this doesn’t mean that the Wind Hashira doesn’t have his moments that make fans want to punch his lights out. It’s clear from the very introduction of this character that he isn’tout to make any friends, and the heartless way in which he tortures Nezuko showcases his sadistic side, turning him into Tanjiro’s foe in no time.
On top of this, it’s revealed that Sanemi is Genya’s brother but actively shirks him whenever he gets the chance. It’s a heartless act that goes against the bond that siblings should share. While there’s more context surrounding the events that led to their relationship being strained, that doesn’t take away from the evil manner in which Sanemi treats his brother, along with every fledgling demon slayer who crosses his path.
19Kaigaku
Most Evil Act: Becoming A Demon And Causing His Master To Commit Seppuku
Not a lot has been seen of Kaigaku barring a flashback with Zenitsu during his studies under Jigoro, so fans will be surprised to see thisDemon Slayervillain namereplace Daki and Gyutaro as the Upper Rank Six. After encountering Kokushibo and being on the verge of death, he surrenders and asks to be turned into a demon to survive at any cost. This news perturbs Jigoro, who is so ashamed that one of his former pupils became a demon that he commits seppuku.
After learning of this information, all Kaigaku does is laugh and berate his former sensei, showing just how self-centered he is. Watching his fight against Zenitsu is going to be an epic encounter for the ages that will prove once and for all who deserves topass down the art of Thunder Breathingto other users.
18Hantengu
Most Evil Act: Commiting Numerous Murders And Never Taking Responsibility For Them
It’s only a given that the members of the Twelve Demon Moons are bound to be quite evil in their own right, and Hantengu is no exception to this golden rule. Fans saw how evil this character is inthe Swordsmith Village arc, with his power being truly astounding in every way.
Before he was a demon, Hantengu was a thief and killer who always tried to deflect any blame from himself by convincing people that he was twisted in the head. While this was the truth, this in no way excused the fact that Hantengu is a psychotic killer who reveled in the act of destroying lives and eating humans to become as strong as possible.
17Kokushibo
Most Evil Act: Forsaking His Sick Twin Brother And Staying Angry At Him For No Justifiable Reason
Kokushibo is one of the most unique demons in the show, being the demon who holds the highest rank in the Upper Demon Moons. He’s a force to be reckoned with, and fans can’t wait to see this demon in his glory when the anime finally gets around to the arc that covers his battle. The fact that he’s the brother of the man whoinvented Sun Breathingmakes him a great personality who is bound to expand the lore and history of the show in new and exciting ways.
However, there’s no denying that Kokushibo is a horrible entity that feeds off the misery of human beings. His jealousy of Yoriichi led him down a dark path where his insecurities got the better of him. This led to him trading his humanity to become a demon who would use his power for evil, even though he still couldn’t hold a candle to his brother’s ability after taking all these measures.
16Gyokko
Most Evil Act: Murdering Innocent Children And Stuffing Their Bodies In Jars
There’s something especially evil about a demon who revels in the act of eating children, and Gyokko has shown these disturbing tendencies from an early age. After his parents drowned at sea, Gyokko found their corpses and developed an unhealthy obsession with these cadavers, leading to him killing a child and stuffing his body in a jar for his morbid amusement.
While the villagers who ostracized him are also to blame for his downfall, Gyokko certainly didn’t do himself any favors by preferring the meat of children after he was turned into a demon by Muzan. The manner in which he stuffed his victims into pots to turn them into his grotesque definition of art is evil and makes him one of the mostheinous characters inDemon Slayerby a country mile.
15Obanai Iguro
Most Evil Act: Pinning Tanjiro, Forcing Him To Watch On Helplessly As His Sister Is On The Verge Of Being Executed
Obanai is a Demon Slayer, not a demon. However, those who have read the manga will know that he might as well be a demon due to his personality and general attitude toward theDemon Slayer Corps. He’s highly critical of the other Hashira or officials and even forced a heavily injured comrade to stay in the Corps just because.
Moreover, Obanai regards the lower-ranked Demon Slayers as useless, expendable fodder and will likely not hesitate to use them as bait or sacrifice to achieve a victory. One of the few reasons he remains in the corps is that he’s one of themost powerful Hashiraand is a one-man army himself. It’s also worth noting that Obanai’s family is an evil clan that worships snake demons.
14Doma
Most Evil Act: Devouring His Followers, Believing That The Act Would Help Them Reach Paradise
Doma is a chilling Upper Rank demon who looks quite menacing indeed. HisDemon Slayervillain namestrikes fear in the hearts of fans, even though his brainwashed followers relish the act of being eaten by this twisted demon. He is unapologetically malicious to a fault.
He’s seen feasting on the corpses of slain courtesans like they are simple snacks. It’s also worth noting that even his other Upper Rank comrades dislike him. Akaza, for example, finds Doma’s indiscriminate killing of humans distasteful since the former prefers to kill and eat combatants.
13Gyutaro
Most Evil Act: Terrorizing The Inhabitants Of The Entertainment District
Gyutaro was a part of Muzan’s Twelve Kizuki and was the joint-holder of the Upper Rank Six position along with his sister, even though the Demon King believed that Gyutaro had more potential than this. The tragic part about Gyutaro’s evil ways is that he was forced to become like this because of his brutal upbringing.
Gyutaro doesn’t care about anyone else but his sister and would happily harm or torture anyone else. While he isn’t exactly the evilest out of all the high-ranking demons, his disregard for mortal life paired with his skills makes him highly dangerous, even as a corpse.
12Daki
One can even consider Daki as the more evil between her and Gyutaro since she didn’t have as many excuses as her brother.She was raised to be selfishand to only care for herself like a spoiled brat. As a result, she notably caused more trouble for humans than Gyutaro did.
Daki ran the Entertainment District with fear, killing any courtesan or civilian out of her whim or due to a mere tantrum. She even treats her brother badly and doesn’t mind calling him ugly or disowning him despite being too dependent on him.
11Swamp Demon
Most Evil Act: Kidnapping And Devouring Women
There was bound to be a demon who used his power to traumatize victims and become a menace to society because humans couldn’t stop him anymore. The Swamp Demon is one such individual, and he’s one of the most wicked demons in the series since he prefers his victims to be girls or young women.
To that end, he’s like the local Jack the Ripper in this Meiji-era Japan, except more disgusting since he also choosesyounger targets, specifically 16-year-oldsand below. While other demons had some tragic backstories that sort of justified their crimes, the Swamp Demon is despicable to the core.
