The Demon Slayer manga has concluded, and the anime's second season bowed in early 2022, but the series has recently made headlines celebrating Tanjiro's birthday with a special art promotion depicting Tanjiro's flight in his attempt to rescue his sister Nezuko.

With Nezuko being the focus on the promotion, the Demons of Demon Slayer have stirred much talk about which of the upper moons would make an appearance in the anime's upcoming third season. And while it will be more of a self-contained arc, the third season will no doubt share insight into the affairs of some of Demon Slayer's best demons.

Tamayo

Image of Demon Slayer character Tamayo using her Blood Demon Art.

While searching for a cure for his sister Nezuko, Tanjiro encounters Tamayo, who despite being a very old and powerful demon, spends her immortality in search of a cure to once again become human. Tamayo is an exceptionally skilled doctor with centuries of expertise and often provides aid to the main characters after particularly dangerous fights.

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Before Tamayo's introduction, Nezuko was the sole demon without the mindset to kill humans indiscriminately for food or power. Instead, she serves as one of the best reminders that Demons were once human, with an internal kindness that outshines even the noblest of Demon Slayers, and endearing her to fans of the series.

Enmu

Demon Slayer Twelve Demon Moons Enmu standing on top of the Mugen Train.

Introduced in Demon Slayer: The Movie — Mugen Train, Enmu is one of Muzan's Twelve Demon Moons holding the position of Lower Rank One. Enmu used his Demon Arts Sleep Inducement, and Dream Manipulation after fusing with the Mugen (Infinity) Train to lure the passengers to sleep and eat them. The large number of humans he ate made him an exceptionally difficult demon to fight and led to the death of many Demon Slayers.

While Enmu is often overshadowed by other Demons, his role in the Mugen Train movie propelled him to heights beyond what he attained solely through the manga. Enmu was able to properly display the full extent of his powers and abilities which are some of the most difficult to counter which boosted his popularity among Demon Slayer fans.

Rui

Image of Demon Slayer character and Twelve Demon Moons Rui using his spider like Blood Demon art.

Rui was Tanjiro's first true encounter with the Demon Moons previously holding the rank of Lower Moon 5. When Tanjiro and the gang find Rui, they discover the mountain he made his home was covered in his spider-like threads and filled with other demons he called his "family." The large number of deaths Rui and his family caused convinced them that the only option they had was to defeat Rui in one of the most visually impressive anime fights of all time to stop the mass slaughter.

Rui acts as a foil to Tanjiro by displaying what an unhealthy family dynamic would look like in comparison to Tanjiro's wholesome family dynamic. Rui's intent of keeping the family together at the expense of the group's happiness in comparison to Tanjiro's and his mother's selflessness served to further legitimize Tanjiro's self-sacrificial character dynamic.

Gyuutaro

Image of Demon Slayer character and member of the Twelve Demon Moons Gyuutaro.

Gyuutaro is Daki's older brother, and together they share the rank of Upper Demon Moon 6.  Gyuutaro is by far the stronger sibling, capable of fighting both the Sound Hashira Tengen Uzui and Tanjiro simultaneously in one of Demon Slayer's best episodes while having them on the defensive. Gyuutaro wields dual Poisoned Blood Sickles with extreme expertise from which even the slightest scratch could lead to almost instantaneous death.

On top of being an exceptionally strong Demon, Gyuutaro is shown to be what Tanjiro would have become if he had decided to hate and curse the world when Nezuko was injured. While Gyuutaro chose to become a demon, his wish for the power to kill those who hurt his sister makes him exactly like Tanjiro, a hurt older brother who wanted nothing more than to protect his sister.

Daki

Image of the Demon Slayer Twins and Twelve Demon Moons Daki and Gyuutaro, while Gyuutaro carries her on his back.

Daki is Gyuutaro's younger sister and hides her demon activities through the prestige she gained from being the Entertainment District's most famous Oiran, Warabihime. Along with her resistance to death through decapitation, her ability to transform into a sash as sharp as a sword and flexible enough to resist being cut made her an exceptionally difficult Demon to kill.

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Opposite Gyuutaro, Daki was created to be a foil to Nezuko. While Nezuko was conditioned to think fondly of humans, Daki's intense hatred of humans is fueled by the atrocities they committed against her. All Daki wanted was to live in peace with her brother, and when that was taken from her, she decided to take brutal revenge on the world.

Kokushibou

Image of Demon Slayer character and member of the Twelve Demon Moons Kokushibou standing menacingly in front of a full moon.

Kokushibou is one of the oldest demons in the entire Demon Slayer series holding the rank of Upper Moon 1. During the Infinity Castle Arc where Kokushibou makes his first true appearance, his overwhelming strength was revealed to be the byproduct of his Demon Powers, over 500 years of battle experience, his former past as one of the Strongest Demon Slayers to have ever existed, and his wielding of one of the strongest Demon Slayer swords.

Kokushibou is a fan-favorite for his contradictory existence as both a demon and a former demon slayer who chose to become a demon to surpass his brother, the strongest demon slayer. In the manga, his famous battle is spectacularly drawn, and fans of the series have become exceptionally excited to see his long-awaited debut in the anime.

Muzan Kibutsuji

Image of Demon Slayer's main antagonist Kibutsuji Muzan in his first series appearance.

Muzan Kibutsuji is the Oldest Demon in all of Demon Slayer at over 1,000 years old and is predominantly responsible for the creation of every other demon in the series. He is the main antagonist of Demon Slayer and the personal archenemy of Tanjiro and Nezuko. Muzan personally killed the entire Kamado Family and turned Nezuko into a demon, presumably in the hope she would kill Tanjiro and then die herself.

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In comparison to other demons such as Akaza and Doma, Muzan is somewhat lacking as a villain. However, his role as the main antagonist, progenitor demon, and Tanjiro and Nezuko's arch nemesis make him a fan-favorite character regardless. And with UFOTable's exceptional animation style, Muzan's impending fight with the demon slayers as the end of the anime increasingly draws nearer, has the fan,s excitement to truly see Muzan fight soar.

Doma

Image of Demon Slayer character and member of the Twelve Demon Moons Doma.

Doma, Upper Rank 2 of the Twelve Demon Moons, is by far the most loyal of Muzan's subjects, despite Muzan's dislike of him. To attain his strength, Doma founded the Eternal Paradise Faith where he would draw in unsuspecting humans to have a constant supply of fresh humans for him to feast on, which lead him to become intertwined with and become the mortal enemy of many Demon Slayers and their families.

While all demons are ruthless and bloodthirsty, Doma in particular with his lack of empathy is the closest to an actual demon with many others often being humanized. His cold-blooded, unfeeling, and gleeful killing of anyone, even those he seems to cherish, makes Doma easily the most terrifying of all the demons in Demon Slayer.

Akaza

Image of Demon Slayer character and member of the Twelve Demon Moons Akaza.

Akaza made his introduction in the Demon Slayer: Mugen Train Movie, where he faced off against the Flame Pillar Rengoku. Despite killing off one of the most beloved characters in all of Demon Slayer, Akaza's backstory, revealed during the events of the Infinity Mansion Arc, has made him a potentially more sympathetic character than even Tanjiro.

Beyond even Gyuutaro, Akaza is the perfect foil to Tanjiro. Akaza chose to gain power to kill everyone after the death of his loved ones, unlike Tanjiro who wanted revenge but only held malice towards Muzan. For this reason, as well as being one of the strongest demons in Demon Slayer, Akaza is by far the best-written character in all of Demon Slayer, even more than Tanjiro himself.

Nezuko Kamado

Demon Slayer Slit Image of Nezuko in Adult, Teenager, and Child Forms.

Nezuko is the younger sister of Tanjiro who was transformed into a demon after Muzan killed their entire family. After spending two years asleep, Nezuko was influenced to think all humans are her family, often putting her demon abilities to great use fighting alongside her brother to kill evil demons while searching for a cure to turn her human.

As the only Demon besides Tamayo who acts purely for the benefit of humans, Nezuko is one of the most unique and complex demons in the series. Instead of wallowing in the suffering of losing her family, she constantly comes to the aide of her brother, almost dying multiple times trying to save him at the cost of her own body, endearing her to fans and making her one of the most popular characters in the series.

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