The Hashira are the pillars of the Demon Slayer Corps. They are it's strongest warriors, who aim to eradicate all the demons in order to protect humanity. This group is under the direct control of Kagaya Ubuyashiki, and he only allows the strongest of Demon Slayer's to enlist in its ranks.
These pillars are constantly searching for a successor, to one day pass on their techniques to. This is maintained throughout history so that the Demon Slayer Corps continues to gain strong fighters throughout the passage of time. To become a Hashira, a Demon Slayer must defeat one of the Twelve Demon Moons or defeat 5o demons, while undergoing intense training (which often takes up to 5 years for a normal person).
Mitsuri is is the current 'Pillar of Love' in the Demon Slayer world. With her interesting breathing technique, she has defeated many enemies in her time as a demon slayer. Mitsuri is a very soft and passionate person, regularly thinking positive thoughts about those around her. Despite her title of love, Mitsuri does not hesitate in the presence of a demon. Instead, she flips a switch and becomes even more deadly. She's desperately on the hunt for a husband but has so far failed. She's a special combatant with skin denser than your average human and when she uses her Demon Slayer Mark, her power increases exponentially.
4 KANAE KOCHO
Kanae was the former Flower Pillar in the Demon Slayer Corps, as well as the sister of former Insect Pillar, Shinobu Kocho. Kanae was one of the few mentally stable Demon Slayers, regularly flaunting a beautiful smile on her face. A loving and caring girl, she always makes sure to take care of her sisters, Shinobu and Kanoi Tsuyuri (adoptive). In her lifetime, Kanae deeply hope that the world would get to a place where humans and demons could peacefully co-exist, despite their shared history of bloodshed. Kanae has not been seen fighting often in the series, but her place in the Pillars is a testament to her skills.
Jigoro is Zenitsu's master and the former Roaring Pillar. He's currently an elderly, so his strength as significantly waned due to the passage of time. But, as a master of the secret techniques of demon slaying, he still holds a considerable amount of knowledge that he can pass down to the next generation. Jigoro is a determined master, who earnestly tries to pass on his teachings to Zenitsu. Due to his experience as a Demon Slayer, he believes he has to prepare the next generation to combat the threat of Muzan Kibutsuji. In his prime, Jigoro used the lightning breathing technique to deadly effect, before retiring due to old age and injuries.
An oddball, even amongst this emotionally unstable force of Demon Slayers. Shinobu was the former Insect Pillar of the Demon Slayer Corps and sister to the fallen, Kanae Kucho. Shinobu wasn't like many other Demon Slayers, her lack of physical strength meant that she couldn't sever the heads of demons in order to defeat them. To compensate for this, she developed a fighting style that relied on piercing and thrusting. She uses this to inject different types of poisons into her enemies, with them often dying in confusuion. She also held an incredible amount of medical knowledge in her head which was of great use to the corp.
Muichiro Tokito is the former Mist Pillar of the Demon Slayer Corps. He has been of considerable use to the Demon Slayer Corps and relies strictly on logic to resolve his missions. He strongly believes that emotions should not play a part in the process of Demon Slaying. Despite his logical ways, Muichiro can sometimes be seen to act in an illogical manner, often wondering off on his own or getting lost in his own mind. Despite these quirks, he's effective as soon as it comes to defeating demons. Muichiro was strong enough to easily defeat an upper moon after awakening his Demon Slayer Mark.
3 OBANAI IGURO
Obanai is a strict man, who adheres closely to the rules of the Demon Slayer Corps and serves as it's current Snake Pillar. He's known to openly chastise and criticize those who do not follow the rules of the Demon Slayer Corps. He also encourages his comrades to throw away their lives for the Demon Slayer Corps, believing it is their duty and he doesn't hold back his words, even to his fellow Hashira. Despite his cruel ways, Obanai has shown to be caring towards Mitsuri and Kagaya. Obanai's snake breathing style allows him to adopt much of the slithery techniques of a snake, making him a dangerous combatant.
2 TENGEN UZUI
Tengen is a former Sound Pillar, having retired from official duty after suffering heavy injury in a battle against a member of the Upper Demon ranks. Tengen is an overly flamboyant character, who is almost always up to something interesting. His rank as a former Pillar speaks for his strength, but his leadership skills were also a great asset to him during his years of active service. Though he's currently retired and married to a couple of different women, he still works hard to assist the Demon Slayers in their missions. His sound breathing techniques make him a deadly foe for the strongest of demons.
Kyojuro was the most recent Flame Pillar. Before dying in battle, he was known to be one of the Hashira's with insane potential. Kyojuro was raised well by his parents and they taught him that the strong should always try to protect the weak. He was known to cheerfully go about his duties as a Pillar and was always willing and able to lend a helping hand during times of need. This sometimes led to his most eccentric trails leaking out, but his strength and dedication meant nobody really paid mind to his odd ways. His strength rested in the fact that he extensivly practised his breathing technique, polishing it into a deadly weapon.
Sankonji is the former Water Pillar and master of the Tomioka and Tanjiro. He's one of the first people associated with the Demon Slayers to be revealed. As a master swordsman, Sakonji has a wealth of experience and knowledge to pass down. As such, he often serves as a trainer for aspiring Demon Slayers. Like Tanjiro, he possesses an exceptional sense of smell which can often be a great help during the battle. He's responsible for passing on the water breathing technique, which has saved both Tanjiro and Tomioka on numerous occasions. Though he is now elderly, he still wields considerable power at his disposal.
Sanemi is the older brother of Genya Shinazugawa and the current Wind Pillar of the Demon Slayer Corps. He's known for being obtuse, quick to anger and somewhat hard to please. Due to trauma concerning demons, he is incredibly distrusting towards them. Having lost much of his family to demons, he's developed a strong hatred for them and refuses to accept the notion that he two factions could eventually come to live in peace. Sanemi has a rare type of blood that is extremely alluring, even to the strongest of demons and he often uses this to lure them in before quickly executing them. The combination of his wind breathing and Demon Slayer Mark has led to him becoming one of the most promising Demon Slayers around.
1 GIYU TOMIOKA
Giyu is a disciple of Sakonji Urokodaki, having learned the water breathing techniques from the master swordsman. Using these abilities, he displayed his strength and was eventually given the position of Water Pillar. Giyu has gone a long way in mastering these techniques and, oftentimes, he completely overwhelms the demons he faces. Giyu can often be reserved due to him struggling to express himself, but he has a kind and sincere heart. His Demon Slayer Mark greatly increases his fighting strength and, in time, he might become one of histories strongest Demon Slayers.
Gyomei is regarded as the strongest current Hashira, having been recruited to its ranks by Kagaya Ubuyashiki. For a long part of his life, Gyomei was just a regular blind man until a demon attacked him at the temple, where he lived with orphan children. The demon was invited into the temple and killed several of the children living there. Gyomei, angered by this loss, went into the offensive and this is when he found out he was remarkably strong. Even the strongest of demons have come to recognize the strength of Gyomei and his stone breathing technique. That technique, his physical strength and his Demon Slayer Mark combine to create the most formidable of Demon Slayers.