The only character I own throughout the entire story is Moriko
Hiei was staying at Kurama's place, in the spare bedroom. One day, he didn't quite get his door completely shut as he was leaving. Yusuke caught sight of this and, knowing Hiei was out, decided to take a look inside. To his surprise, it was almost exactly the same as he'd seen it before, with only a few telltale signs that someone was actually living there: the bed was unmade, there were a couple pieces of clothing hung over the back of a chair, a picture of Yukina sat on the bedside table. All impersonal enough that the room could have belonged to anyone. Kuwabara, for example.
As he was turning to leave, the sun glinted off something lying next to the pillow, catching Yusuke's eye. Curious, he turned around to see what it was. To his surprise, it was a simple, tin box, about the length and width of a paperback book, probably an inch deep. Yusuke wandered over and picked it up. On the top, Jaganshi Hiei was written in small, neat lettering. Still curious, and because that's what he did, Yusuke took the box with him and left the room. He had touched nothing, excluding the box and doorknob, so the disappearance of the box was the only thing different.
And when Hiei returned, the thing he valued almost more than anything, second only to his katana, had vanished.
Yusuke had gone home by then, the small, tin box in tow. He noticed it was very light, as if nothing was inside of it. When he opened it, however, he found that it was almost full. And it was filled nearly to the top with something he hadn't suspected, something he never would have guessed. Hiei had a box of… letters. Why? Why had he kept them so long? They were obviously old. Judging by the fact that they were yellowing and the edges were frayed, they were very old. Not to mention the detail that what they were written on wasn't so much paper as it was parchment. They had to be a hundred years old, at least.
Without looking at the signature at the bottom, Yusuke deduced that it couldn't be Yukina. She had no idea Hiei was her brother. Yusuke resolved to read them in order to find out who was important enough to Hiei for him to have kept the letters they wrote to him for all these years.