Kagaya Ubuyashiki, the leader of the Demon Slayer Corps, is marked by his gentle, compassionate, and wise demeanor that covers supernatural inner power and obstinacy towards Muzan in spite of being plagued by a debilitating illness.
He functions as a spiritual anchor where he treats Slayers as family, hopes and strategically leads them with deep empathy in true strength through with his purpose and selflessness, even suicides himself for a trap for Muzan.
Appearance
Kagaya was a man of stunted physicality and of medium stature and very pale skin complexion. He had shoulder length black hair which was parted in the middle.
Due to his family curse, Kagaya averted his eyes and looked like he’s rotting alive with large parts of his skin in a sickened, shriveled, pink color that started from his left side of the forehead and gradually transitioned across his body.
In addition to this curse, it caused him to go blind as it effects his eyes, turning his sclera from white to black (light purple in the anime) and his pupils from a dark purple to a light purple, matching his cursed skin.
When he was first formally introduced in Tanjiro Kamado’s trial, Kagaya’s curse covered only the top half of his head, but during the last moments of his life, only months later, the curse has spread to his entire body, leaving him covered completely with bandages apart from his mouth to speak.
Personality
Kagaya had a calm, dedicated and composed demeanor, showing genuine care about the members of the Demon Slayers whom he considered as his children.
He was also able to deal well with criticism and was frank about his weaknesses; one being his inability to one become a Demon Slayer despite being their main leader.
In order to make up for this, he remembered every single member of the Corps and visited the deceased members at their cemetery on a daily basis until he could no longer move due to his illness.
While he may appear to be lenient, he only shows due consideration to reason and if there was no bias present in a situation, as seen when he showed such acceptance and willingness for a situation of Tanjiro and Nezuko via a letter from Sakonji Urokodaki and defending their case when most of the Hashira respectfully disagreed with his pardoning.
His manner of speaking was generally fluid and gentle, extremely tactful and deliberate and the use of words and intonations was in a manner that the people he talked to, he wanted to listen and wanted to listen to.
This was because his insightful and charismatic speech was able to make the likes of the initially passive Muichiro Tokito and the impulsive Sanemi Shinazugawa listen to what he had to say without him conveying anything that might rile them up.
Towards his own kin, in this case his children, Kagaya was rather strict. Due to the curse of their family, he had to prepare them early on to take over his life of leading Demon Slayers.
It is also worth noting that Kagaya himself has taken the stand as Oyakata after the suicide of his father at a mere age of four, and was further plagued by the double-suicide of his siblings and the accidental death of their mother in the process.
Abilities
Emotion Masking:
Kagaya had the amazing power to cover up his feelings and hold a respectful and emotionless outward appearance. He made use of this ability to keep a level and peaceful mind and fool other people’s understanding of him.
When Muzan, who was the focus of Kagaya’s deep hatred from the bottom of his heart, confronted him at his house, Kagaya went along with the serene smile of Buddha that hardly hid any evidence of killing intent.
By thus thoroughly destroying his fighting spirit, animosity, and hatred, Kagaya managed to hide his real purpose and lured Muzan into a trap.
It wasn’t until Kagaya sacrificed himself by using an explosive in order to entangle Muzan that the demon made sense of the depth of Kagaya’s hidden emotions; he compared Kagaya’s concealed violent intention to the coiled viper in his lifeless stomach, in awe of Kagaya’s unbelievable ability to cover his true nature.
Soothing Voice:
Kagaya not only had the power to put others at ease by just the sound of his voice and movement of his action as he showed to Tanjiro Kamado and even to the angered Hashira.
In modern times, this attribute is called 1/F Fluctuation, and is said to be possessed by many charismatic people and have the strength of presence to move mass audiences.
Supernatural Abilities
Extrasensory Perception:
Kagaya is armed with the ability to detect the presence of human and demon as well as know their strength. This was made obvious when the Hashira meeting took place after the events at Mount Natagumo.
Despite losing vision in both eyes from the development of his illness, Kagaya immediately felt the number of people with the power of Hashira when they arrived and expressed his satisfaction that they all made it to the meeting without personnel changes.
Furthermore, when Muzan came to the Ubuyashiki Estate intending to kill him, Kagaya immediately detected the presence of Muzan and greeted him despite his eyes being completely covered by bandages and Muzan being standing at a distance outside of the Estate displaying his extraordinary sensory abilities.
Foresight:
Kagaya, as well as the rest of the Ubuyashiki family, possess a heightened level of foresight that help them avoid disastrous situation, which amassed them a great amount of wealth and fortune.
Due to this instinct, Kagaya accurately made several guesses regarding multiple things which were eventually proven to be true and accurate without him knowing any prior information, as seen when he accurately predicted that Muzan’s only remaining weakness was the sun and that he could not be destroyed by decapitation, that the deaths of Gyutaro and Daki would send waves that would eventually see that the Upper Ranks of the Twelve Kizuki begin losing members for the first time in hundreds of years, and that Muzan will find him and bring about the final war between Demon Slayer Corps and the Twelve Kizuki during his last
