Demon Slayer season 3 is set to begin on April 9, 2023, with a one-hour special. With everything that's happened in the characters' lives so far, it's easy to forget just how young they are.
Nezuko and Tanjiro are still barely in their teens to have gone through so much and still be standing and fighting off the many demons they had to fight.
But several others that are older and younger than the main protagonists, like Zenitsu and Kotetsu, should be counted, and this list will detail them.
Disclaimer: As this list will deal with manga and anime characters, there will be major Demon Slayer spoilers. The opinions reflected therein are only those of the author. As some of them are the same age, other factors will determine their rank.
Inosuke Hashibira, and 9 other youngest characters to be featured in Demon Slayer season 3, ranked from oldest to youngest
10) Kozo Kanamori (26)
The oldest of those set to be featured in Demon Slayer season 3 is Kozo Kanamori. Kozo is 26 years old and a swordsmith affiliated with the Demon Slayer Corps in Swordsmith Village.
He's extremely soft-spoken, but still able to fight since he makes swords for a living. He proved this by defending Hotaru Haganezuka from the fifth Upper Rank demon, Gyokko.
Befitting a swordsmith, he can be hot-tempered and passionate when it comes to the swords he forges. This is shown in Demon Slayer's manga, specifically chapter 51, where Inosuke Hashibira purposefully chipped the dual blades the swordsmith received from Kozo and earned a loud berating as a result.
He also vowed to fix the rusted blade that was inside the Yoriichi Type Zero.
9) Giyu Tomioka (21)
Alongside Mitsuri and the still-to-be-introduced Muichiro, Giyu Tomioka is a major supporting character in Demon Slayer season 3. He's so major throughout the series as the Water Hashira that he got his own spin-off.
Giyu is one of the high-ranking Demon Slayers, controlling and using water to his advantage with his Water Breathing Style.
It should also be noted that he played a pivotal role in Muzan's eventual defeat in the manga, and likewise he helped hold off Tanjiro long enough to help him become mortal after he was turned into a demon. Giyu isn't to be messed with, as several demons have shown no match for his speed.
He's also more pragmatic than most, recognizing the nuanced situation Nezuko and Tanjiro are in.
8) Mitsuri Kanroji (19)
Don't let the look fool you, Mitsuri Kanroji is really 19 years old. She's also incredibly jovial and has earned her title of Hashira of Love for being quite the gentle person and wearing her emotions on her sleeves. She's introduced in the upcoming Demon Slayer season 3.
Mitsuri showed no mercy to any demons that came her way. She's got muscle density eight times denser than a regular human, making her incredibly physically strong, and able to stand against powerful Upper Rank demons.
She even caught Muzan off guard by managing to rip one of his arms off. She may have died during the final battle but she went down swinging.
7) Genya Shinazugawa (16)
Another major supporting character in Demon Slayer season three is Genya Shinazugawa. Genya was initially foul-mouthed and brash, with no real manners or sense of decorum around others.
That changed during the Swordsmith Village arc where the Fourth Upper Ranked demon of the 12 Kizuki, Hantengu, gave him far too much trouble to handle on his own.
Following this encounter, Genya cooled off and became more sociable. He even saved Tanjiro's life against Hantengu, as Tanjiro saved his when the two encountered a splitting demon named Aizetsu.
His sibling rivalry with his big brother Sanemi was also a key part of why he was so brash, as they had a falling out following a demon attack on their family.
6) Kanao Tsuyuri (16)
So, normally Zenitsu would be featured in this part of the list since he's a main character. The problem is that he doesn't feature in Demon Slayer season 3, having been off on a mission with Inosuke.
This particular entry will then zero in on Kanao Tsuyuri, who had to take care of Tanjiro following the events of the Entertainment District Arc.
Kanao is a Demon Slayer herself and mostly aids Tanjiro on his journey despite initially trying to kill him and Nezuko during the Final Selection. She had to look after him during the months he was in a coma, and even managed to be one of the last conscious during the battle with Muzan. She was also happy to see Tanjiro awake and yelled that everyone was crowding him when he tried to sleep.
5) Inosuke Hashibira (15)
One of the main characters that's hated by more than a few uniform makers and swordsmiths is Inosuke Hashibira. Despite appearances, he is human beneath the hollowed-out boar's head he wears as a mask. Inosuke and Genya might as well have been separated at birth, given that Inosuke is hot-tempered, abrasive, proud, and vengeful.
He was also raised by boars, which likewise justifies his rude personality. He couldn't write or read at the time of his debut and struggled to understand and remember people's names.
He does, however, cool off thanks to his friendship with Zenitsu Agatsuma and Tanjiro Kamado. Although mostly absent for the arc featured in Demon Slayer season 3, fans won't have to wait long to see him again.
4) Tanjiro Kamado (15)
The literal main character alongside Nezuko, Tanjiro Kamado started his and Nezuko's perilous journey after Muzan attacked and slaughtered most of their family. After surviving an attack from a Demon Slayer, Tanjiro went out of his way to train with them in order to cure Nezuko of her demonism and kill Muzan.
During Demon Slayer season 3, Tanjiro was knocked into a coma after a battle between the Upper Moon demons Daki and Gyutaro. It took him two months to fully awaken, and a further week to get moving with a full recovery.
Being out of it when it comes to a huge battle isn't quite normal for a shonen protagonist, but it's nothing out of the ordinary for Demon Slayer.
3) Muichiro Tokito (14)
Introduced in Demon Slayer season 3, Muichiro Tokito is arguably the youngest in the Demon Slayer Corps. Muichiro is also notable for two things: the current Mist Hashira and also a descendant of Muzan's right-hand man Kokushibo.
The first means he's a high-ranking Demon Slayer, specializing in Mist Breathing that obscures his movements with mist and allows him to get the drop on enemies.
The second is something that he's not entirely proud of and gets blindsided by when he meets Kokushibo. He and Tanjiro get into a brawl and have an antagonistic start given that he was being rude and hit Tankiro hard enough to knock him silly.
He does, at least, decapitate a high-ranking demon at the end and helps Tanjiro out with another one.
2) Nezuko Kamado (12 physically; 14 chronologically)
Nezuko Kamado is an odd case to talk about. She's effectively the baby out of the group of Tanjiro, Inosuke, and Zentitsu. She's also feral when her demon powers come out.
She was turned into a demon by Muzan and thus stuck in a 12-year-old body. This made her an ideal target for Demon Slayers, which is why Tanjiro has to carry her around hidden in a basket and to hide her from the sun.
But just because she's petite looking doesn't mean she skimps out on fighting. Her demon form allows her to fight on an even plane with the 12 Kizuki, giving enhanced speed and sharp nails.
Of particular note is her pryokinesis with her Blood Demon Art since she's been key to stopping and burning through many demons like Rui, Enmu, Daki, and Hantengu. By the time of Demon Slayer season 3, she becomes immune to the typical demon weakness of sunlight.
1) Kotetsu (10)
The last and youngest character to be featured in Demon Slayer season 3 is a young kid in Swordsmith Village. His ancestors built the battle doll Yoriichi Type Zeo, which ends up being a secret weapon and trained on by both Muichiro and Tanjiro after Kotetsu repairs it. He's kind and energetic and is an orphan.
Tanjiro helped give him the strength and willpower he needed to finish repairs on the Type Zero. This was included even after Tanjiro beheaded the combat doll. He also has help from Muichiro after demons assaulted the village, providing the first push the Mist Hashira needed to be a better person.
Kotetsu features prominently in Demon Slayer season 3, as a supporting character.
To conclude, these have been 10 of the youngest characters featured and present in some way in Demon Slayer season 3. Some are major characters like Muichiro, Tanjiro, and Genyu, while others are supporting characters like Kotetsu. It says something that the youngest to be affected by the events is 10 years old, as Demon Slayer hasn't been known to pull punches on children in peril.
As Demon Slayer season 3 is on the horizon, premiering on April 9, 2023, with a one-hour tv special, now would be the time for fans to catch up before it premieres.
Demon Slayer season 3, as well as prior seasons, can be viewed on Crunchyroll and Funimation's streaming service. Prior seasons are also available on Hulu and Netflix.