After the battle with Akaza, Kyojuro couldn't kill him and sustained critical injuries but miraculously survived. He rehabilitated along side you and his father's bitterness had also lessened after almost losing his son. Kyojuro had become stronger strength wise, but he had lost his left eye so he was a bit vulnerable which gave you a reason to protect him more.

He was back on service, training demon slayers since Nezuko had overcome the sun, so the final battle was close as Muzan would try to get her to archieve the same. But now you two were running towards Oyakata-sama's house after getting the message of him being in trouble. You followed your crows but it was too late. A massive explosion was heard and the master's house was already in flames. Upon arriving to look for survivors along with the other hashira and Tanjiro, Gyomei was already fighting what he said was Kibutsuji Muzan.

Everyone's blood boiled as Sanemi taunted Muzan in anger. As if on command, the moment Tanjiro screamed in anger everyone moved to attack but to everyone's surprise, Muzan smirked as a door opened below everyone's feet as they slipped into the infinity castle, falling endlessly.