Kagaya has light skin and black shoulder length hair. He has a curse mark that is slowly killing him that also makes his skin look as if it was rotting spreading down his face and covering his eyes making him unable to see, by the time of his death this curse had spread all over his body making moving nearly impossible. Muzan at Kagaya's death described him as having the smile of a Buddha.
He usually wears a black kimono with a long white kimono jacket with a pink and purple mist like pattern that starts around the lower back/waist.
Kagaya has a calm demeanor; showing genuine care about the members of the Demon Slayers, even considering them as his children. He is also able to handle criticism well, and is honest about his weaknesses; one being his inability to become a Demon Slayer despite being their main leader. In order to make up for this, he remembers every single member of the corps and visits the deceased members at their cemetary on a daily basis until he could no longer move due to the curse.
While he may seem lenient, he gives due consideration to reason; clear of any biases, shown when he willingly accepted the situation of Tanjiro and Nezuko (via a letter from Sakonji Urokodaki) and even defending their cause when there are others who thought otherwise. His manner of speaking, while generally fluid and gentle, is extremely tactful; using words and intonations in a way that the person he talks to would listen. His tactful and charismatic speech is even able to make the likes of the initially passive Muichiro and the impulsive Sanemi listen to what he has to say without saying or conveying anything that would rile them up.
Towards his own kin, such as his children, Kagaya is rather strict due to the curse of their family. He nevertheless shows the same gentle aura and demeanor towards them.
Abilities and Powers
Foresight: In addition to his special voice, Kagaya (and the rest of the Ubuyashiki family) possessed a heightened level of instinct that could help them avoid disastrous situations and amassed them a great amount of wealth and fortune, due to this instinct Kagaya has accurately made several guesses about multiple things that were eventually proven to be true and accurate without any prior information, as seen when he accurately predicts that Muzan's only remaining weakness was the sun and could not be destroyed by decapitation, the deaths of Gyutaro and Daki, would send waves that would eventually see that the Upper Moons of the Twelve Demon Moons will begin losing members for the first time in hundreds of years, and once more when he predicts that Muzan will find him and bring on war against the Demon Slaying Corps during his last five days alive.
- Kyojuro Rengoku states that he is the 97th leader of the corps.