when obanai was younger he had a friend who would visit him in his cage everyday giving him all sorts of treats but when he escaped with his friend and the snake demon caught up his friend left him to die..

”this young 19 year old knows where the blue spider lily is and is being hunted by Muzan kibutsuji. Keep her safe”

ubuyashiki says as all the hashira look up at you, obanai immediately recognizes you as the friend that left him behind all those years back then, kaburamaru lifted his head up in excitement pleased to see you again.