Kyojuro Rengoku is one of the most popular and powerful characters in Demon Slayer: Kimetsu No Yaiba. After the Mugen Train Arc, everyone knows that Rengoku is not someone you mess with.
Rengoku is the former Flame hashira and the son of Shinjuro Rengoku who was also once the Flame Hashira. He has a younger brother, Senjuro Rengoku.
Rengoku, without any doubt, is one of the strongest, if not the most powerful demon slayer in the demon slayer corps.
Rengoku – Abilities
Kyojuro was a skilled and powerful fighter. He was already known to be a great fighter before he took over for his father. He took revenge for the deaths of the nine Demon Slayers who were killed by the Flute Demon by himself. Later, he beat Lower Rank Two Hairo by himself. Before he died, Hairo praised his swordsmanship.
Shinjuro Rengoku, his father, said that after he stopped teaching his son, Kyojuro trained himself to become a Hashira by reading only three volumes of the guidebook for the Flame Breathing style.
Even the Upper-Rank Three demon Akaza, who is the fourth-strongest known demon, acknowledged and praised Kyojuro’s strength.
Akaza also praised his fighting spirit and said that he was getting close to the “Realm of the Highest.” This meant that he was very close to getting the Transparent World and the Selfless State.
Kyojuro’s senses were very well-tuned. For example, he could feel Akaza’s huge presence and demon aura, which helped him figure out that he was an Upper Rank.  Kyojuro could also find demons faster and more accurately than Tanjiro Kamado, who has a strong sense of smell. He found two demons on a train right after each other before anyone else did.
Extreme Speed and Reflexes
As a Hashira, Kyojuro had very fast reflexes and speed. Kyojuro could run so fast that it could even shake the ground and almost throw a train off its tracks.  Also, Kyojuro could easily move faster than the eye can see, cutting off the heads of demons before they even had a chance to react. Because he moved so quickly, he was able to cut Akaza’s arm just as the Upper Rank was about to hit Tanjiro.
Immense Stamina and Endurance
Throughout the series, Kyojuro’s fights showed that he had more stamina and endurance than a normal person. In his Special One-Shot, Kyojuro broke his eardrums, but he didn’t even flinch. He kept fighting through the pain and won.
As a Hashira who had spent years training to improve his physical skills, Kyojuro had incredible strength. He could swing his katana at speeds faster than the eye can see. Kyojuro also had very strong hands, which helped him hold down Akaza, who was one of the strongest characters in the show.
Kyojuro had a strong will that couldn’t be broken. Even Upper Rank 3 Akaza was impressed by this. Because he had promised his late mother when he was young, he had always had a strong will and a lot of drive.
Kyojuro was one of the best and most powerful swordsmen in the whole group. He is also a member of the Rengoku family, which has a long history of powerful swordsmen, including Flame Hashira. This gives Kyojuro an advantage when it comes to learning and improving his sword skills.
His skill with the sword was best shown when he fought Akaza.
He was able to fight on the same level as the Upper Rank, who had killed a lot of Demon Slayers and even Hashira over the last century. Akaza was so impressed with Kyojuro’s swordsmanship that he kept praising it.
Rengoku – Breathing Style: Flame Breathing
Kyojuro learned this breathing style from the previous Flame Hashira in the Rengoku Family, Shinjuro Rengoku. He later mastered it by reading the books that the previous Flame Hashira in the Rengoku Family had left behind.
Kyojuro is the best Flame Breather of his generation. Using this Breathing Style to fight, he became very good at it.
First Form: Unknowing Fire
Rengoku charges at their target quickly and lets out a single slash that is meant to cut off their head.
Second Form: Rising Scorching Sun
Rengoku lets his sword swing up in an arc.
Third Form: Blazing Universe
Rengoku makes an arc with their blade as they bring it down.
Fifth Form: Flame Tiger
Rengoku uses his sword to make a series of power cuts that look like a flaming tiger.
Ninth Form: Rengoku
This is the most powerful Flame Breathing skill. Rengoku raises their sword up high and then dashes forward quickly. The technique is strong enough to cut through the ground completely. In the movie and anime version, this technique looked like a Japanese dragon on fire that wrapped around Rengoku as he charged toward the target.
Rengoku – Sword
Rengoku wields a normal Nichirin Katana. It is made from scarlet ore that is a deep shade of reddish-orange and has the words “Destroyer of Demons” carved on the side. On each side of his white-handled katana, there is a clear flame pattern.
Rengoku – Appearance
Kyojuro was a young adult who was tall and built like an athlete. People say he is charismatic and full of hope, and he seems to have a smile on his face almost all the time.
He had long, bright yellow hair with red streaks that looked like flames.
On the side of his head, he had two bangs that were shoulder-length and two that were chin-length. His eyebrows were black and forked, and his eyes were golden that faded to red, and had white pupils.
When he first joined the Demon Slayer Corps, he only wore the standard Demon Slayer uniform. As he moved up the ranks, Kyojuro started wearing a completely white haori before putting on his signature flame-patterned one.
Rengoku – Personality
Kyojuro was very passionate about his job as a Hashira, and he often seemed like a happy-go-lucky oddball. He was friendly, had a good heart, and had amazing swordsmanship and technique that came from hard work and discipline.
Kyojuro also cared a lot about his family. He treated his father, Shinjuro Rengoku, with a lot of respect and worry, even though he was becoming more hostile and uninterested in Kyojuro.
Kyojuro seems very enthusiastic, but he is very smart and good at strategy. He acts quickly and accurately in battle, especially when other people’s lives are at stake.
Last but not least, he hates demons just as much as most Demon Slayers do, usually because they do bad things or have different morals.
Rengoku x Akaza
The Big Fight
Akaza shows up not long after Tanjiro, Rengoku, Inosuke, Zenitsu, and Nezuko beat Enmu and saved the passengers. When he sees that Tanjiro is on the ground, he moves quickly to kill him.
He is stopped by Rengoku, who cuts his arm in half. Akaza fixed the wound quickly and complimented his sword. When asked why he attacked someone who was already hurt, he said that he just wanted to get rid of him quickly before talking to Rengoku. He thinks that as a Hashira, his fighting spirit is at its best, so he tries to turn him into a demon.
He says that if he were a person, he would grow old and die, but if he were a demon, he could keep getting stronger. When Rengoku keeps saying no and disagreeing with Akaza, Akaza gets angry and says he will kill Rengoku instead. Then he uses Destructive Death: Compass Needle.
Tanjiro and Inosuke are watching from a distance as Akaza and Rengoku fight hard. They both know that in terms of strength, the two are very different.
Akaza Trying to Recruit Rengoku
Akaza gets hurt a lot, but his cuts heal quickly. He makes fun of Rengoku by saying that none of the Hashiras he has killed have ever agreed to change after he has asked them to. The demon jumps into the air and hits Rengoku with an Air Type attack, which knocks him back for a moment but quickly stops. Flame Hashira moves quickly forward because he knows it will be hard to fight from afar. He tries to attack close up, but every swing he makes is blocked or avoided.
Akaza makes fun of him again because his human strength is getting weaker compared to his demon strength. He also tries again to get Rengoku to change, but Rengoku keeps saying he won’t be like him. Again, they fight, and Inosuke says that he couldn’t help Rengoku because he is too slow and would die right away if he tried. Akaza starts to attack the Hashira, doing a lot of damage to it.
All of Rengoku’s sword strikes are useless because the demon can heal quickly, and as he keeps using Flame Breathing, he looks more and more desperate. Rengoku gets a chance to catch his breath when Akaza moves away all of a sudden.
But Tanjiro and Inosuke see that Rengoku is bleeding heavily while Akaza is fine and well.
Flame Hashira Goes All In
Akaza makes fun of Rengoku’s many wounds again, even though he had already healed because he was a demon and because he was fighting a losing battle as a human. Rengoku’s body is filled with fire all of a sudden. He tells the demon that he will do his job as a Hashira, which confuses and amazes the demon.
Rengoku decided to try to hurt him as much as possible, even if it meant he would die, and moved quickly with Flame Breathing: Esoteric Art. Akaza is impressed by his opponent’s willingness to fight, so he tells him to change into a demon so they can fight forever. He says that he is the Flame Hashira, then uses Flame Breathing, Ninth Form: Rengoku, and rushes forward.
Akaza uses “Destructive Death: Annihilation Type” in response. Akaza’s arm, chest, and almost all of his neck were cut by Rengoku. On the other hand, Akaza stuck his arm in Rengoku’s solar plexus. Akaza begs him very hard to become a demon. He knows that the wound he gave him will kill him, and he is surprised that his opponent is still fighting.
He tells him that he was chosen because he is one of the few strong people. Again, Rengoku says no, because his mother told him to look out for the weak. He drives his sword deeper into Akaza’s neck and even catches Akaza’s fist when he tries to punch him with his free hand, which surprises the demon.
Rengoku’s Demise (Tanjiro vs Akaza)
Akaza tries to run away as the sun comes up, but Rengoku stops him because he won’t give up. The Hashira need help, so Tanjiro and Inosuke try to help. Inosuke uses Fang One: Pierce to fight the demon.
Akaza suddenly rips his own arms off Rengoku’s body and stomps on the ground. This causes a shockwave that knocks Inosuke away and gives him the chance to run away. Tanjiro quickly chases after the Upper Moon and throws his Nichirin Blade at him. The blade goes through the Upper Moon’s chest. Akaza hears Tanjiro’s screams and calls him a coward for running away.
This makes Tanjiro angry, so he tells himself he’s running away from the sun, not from him. Akaza leaves Inosuke and Tanjiro with a dying Rengoku because he thinks the battle is over and Rengoku will die soon.
Rengoku is no doubt, one of the most powerful demon slayers in Kimetsu no Yaiba. There is no one with a stronger will.
Frequently Asked Questions
When did Rengoku Die?
Rengoku dies while fighting Akaza in the Mugan Train Arc.
What is Rengoku’s Full Name?
Rengoku’s full name is Kyojuro Rengoku. Rengoku is his family name.
Does Rengoku have a Demon Slayer Mark?
Unfortunately, he was not able to awaken his demon slayer mark while fighting any of the demons. Demon slayer marks give an immense boost to demon slayer’s abilities, skills, and strength.