Kyojuro was a young adult of tall stature with bright yellow hair with red streaks, black forked eyebrows, and golden eyes.
His outfit consisted of the regular Demon Slayer uniform along with a white-yellow gradient pattern and red flame-like ridges at the end.
Kyojuro was greatly enthusiastic in regard to his duties as a Pillar and often cheerfully eccentric. He was amiable, kind and boasted extraordinary technique and swordsmanship stemming from strict practice and discipline. He was an honorable warrior who adhered to his code of morals and principles that was instilled into him by his mother at a young age - the most significant being that those who were born strong have a duty to protect the weak.
Kyojuro is the eldest son of Shinjuro. His father was known as the Flame Pillar of the Demon Slaying Corps until his unexpected retirement.
During the Demon Train Arc, it is revealed that Kyojuro has a younger brother who trained alongside him until their father ceased to teach them. His strength is displayed when he defends over 200 people from being slaughtered by the demons. He comes face to face with the Upper Moon Three, Akaza, and battles him head on but is fatally wounded and succumbs to his injuries.
Shinobu Kocho noted that Tanjiro was on trial, which Kyojuro saw no need for as he was protecting a Demon, which was a clear violation of conduct; he stated that it was a matter they could deal with themselves. He then agreed with Gyomei Himejima's idea to kill Nezuko Kamado, witnessing shortly afterward Tanjiro's coughing fit, and remained silent when Mitsuri Kanroji asked if they should be dealing with their subordinate's trial without Oyakata-sama's input. After Tanjiro headbutted Sanemi Shinazugawa, Kyojuro looked at Mitsuri when she laughed with a neutral expression.
Abilities and Powers
As a Pillar of the Demon Slaying Corps, Kyojuro was a very powerful swordsman. Akaza, the Upper Moon Three, acknowledged Kyojuro's strength and offered to turn him into a demon so he could surpass his human limits and become stronger. He also complimented his battle spirit and stated that it was getting close to the "supreme territory" which also meant that he was close to obtaining the see-through world. His father, Shinjuro Rengoku, stated that after his son abandoned what he taught him, Kyojuro trained himself into a pillar after reading through an instruction book of the Flame Breath, a book which only had 3 volumes.
- Master Swordsman: Being a Pillar of the Demon Slaying Corps, Kyojuro is one of the most powerful and skilled swordsmen in the entire organization. Akaza, the Upper Moon Three, was impressed at Kyojuro's highly refined swordsmanship.
- Enhanced Strength: Kyojuro possessed great grip strength that was described as "unbelievable" by Akaza despite the fact he was gravely injured during that time.
- Enhanced Speed: Kyojuro possessed great speed that even a trained Demon Slayer like Tanjiro couldn't see or follow, and could even cause tremors with it. Even Akaza, the Upper Moon Three, was impressed with his speed.
- First Style: Sea of Fire (
壱ノ 型 不知火Ichi no kata: Shiranui?): Kyojuro charges towards his opponent at high speed and decapitates them in one or multiple slashes. This technique had enough force to launch train carriages off the tracks a short distance.
- Second Style: Ascending Blazing Sky (
弐ノ 型 昇り 炎 天Ni no kata: Nobori en ten?): An ascending slash. Kyojuro used this technique to slice Akaza's arm in half.
- Third Style:
- Fourth Style: Wave of Blazing Flames (
肆ノ 型 盛 炎のうねり Shi no kata: Sei en no uneri?): Kyojuro spins his sword in a circular motion, deflecting his enemies attacks.
- Fifth Style: Flame Tiger (
伍ノ 型 炎 虎Go no kata: Enko?): A series on sword slashes that take on the form of a tiger. Kyojuro used this technique to contest Akaza's War Style.
- Sixth Style:
- Seventh Style:
- Eighth Style:
- Ninth Style: Purgatory (
玖ノ 型 煉 獄Ku no kata: Rengoku?) - A devastating dashing slash that Kyojuro initiates from a high stance, the technique had enough power to carve a deep impression in the ground where he used it. Before using this technique he remarked to himself about "thoroughly hollowing out most of the area".
- "You have some great dedication!"
- "I've never seen a swordsman with a black blade become a pillar! "
- "The Red Flame Sword of Rengoku will burn you down to the bone!"
- "He said it was pointless. But! My passion won't die because of that! The flames in my heart will never ever disappear! I'll never be disheartened!"
- "And you're different from me, Senjurou! You have an older brother. And he believes in his younger brother. No matter what path you take,You'll be a wonderful person! With a burning passion in your heart. Do your best! Do your best to live!"
- "As a pillar, I'm ashamed of myself! If there's a hole, I wanna go into it!"
- "Growing old and dying is the beauty of the fleeting creature called a human being. Because they grow old, because they die. They are tremendous. Lovable. And precious. what they call 'strength' isn't a word that is used in regards to the body."
- "Mother, same goes for me. It was an honor to have someone like you give birth to me."
- "If you get knocked down by your own weakness and cowardice, flame up your heart, grit your teeth and move forward. Even if you stop in your tracks and cower, you're not gonna stop the flow of time. Don't be saddened by the fact that we're all reaching the end."
- “Set your heart ablaze!”
- Kyojuro was ranked in 7th place as of the first character popularity poll with 1,021 votes.
- Kyojuro loves to watch sumo wrestling.
- Kyojuro's favorite food is sweet potatoes. When he eats them, he says "Wasshoi! Wasshoi!"
- His favourite side dish is salt grilled bream.