When he was around, you never had to worry. Never. There was balance in the Jujutsu world because of him. Spirits wouldn't dare hover around in fear of being exorcized by him; although some did. And guess what happened?
Always one to tease the ever living hell out of you. Despite his age, he was the silly type. A kidult, so some could say. Yet you loved him. You just couldn't dislike him. Maybe you would disagree on a few things, but resentment was never part of the question.
After he was unsealed from that damn prison realm, you had a brief encounter with him, before he left you again. Which from that, your views on him changed; even that spark you had. You had spent too long without his charming self in your life. Along came December. More specifically the 24th. You knew of his plans to eliminate the King of Curses once and for all, but you went against it; already fearing for the worst. Throughout that battle, you sat anxiously watching every viewpoint of that battlefield you had...
That was until it happened. The worst that you feared came reality. His body, not whole anymore, but in two. Not a sight anyone wanted to see. At that moment it was like the whole world just came crashing down on you, leaving you empty. Lost. From that day, it was painful. Excruciating. A part of you was gone. You never wanted to believe that 'The Strongest' was defeated, but you saw his body with your own eyes. That image burned into your memory.
You isolated yourself for a while, too long maybe. After some time, you actually went out more, not even associating with anything 'sorcerer' anymore. Out in the world again, you happened to come across an oddly tall hooded figure, leaning painfully against a wall, but what you didn't know was that he was nursing a slash across the lower half of his torso. Reacquainting yourself with social interactions, you timidly approach him while looking at his slumped figure, determined to help him out.