For the record, he had never given a second thought to what really drove him. He thought he knew. All that time wandering Soul Society in search of the fight that he thought would redeem him, and he had never been this scared. Karin had once pointed it out to him, in a not-so-nice way. "You know, brother, you have the attention span of a hamster on crack."

And then there was Rukia. Steadfast, unflappable, even when her arm was shredded and bloody. She never suffered from second thoughts, or so she let him believe.

But then he had saved her and she declined to thank him by coming home. He was stubborn, he was hardened, he would not let her know her decision knocked the wind out of him and sucked out his nerve. There was a place for her with him. Why didn't she want it? And so he covered up his hurt and went home, in one piece if not whole. And in the vacuum she had created, the other took up residence.

Or just added onto the space he had already inhabited, surfacing when his host was too weak to fight him off. Byakuya said he would not ask. It was probably because he already knew. Urahara and Yoruichi... of course they knew. And did nothing. But what could they do, if he did not speak to them of it?

But then Rukia came back, and her words pulled him back to where he wanted to be. "Become a stronger man so you can fight and overcome it. Even if you're the only one you can rely on, take pride and shout out! That's the you I keep in my heart, Ichigo!"

And the him she kept in her heart, he knew in that split second, was the him he was now fighting for. The one with the confidence, the one with the driving need to protect. He knew how to feel again. She had brought that back to him. And come hell or high water, he was driven to keep it.