I think someone said that his empress might also be a former dragon, which would explain why their relationship is sort of.... okay?
I mean, I understand why he's become the way that he is, but if the white dragon really ends up with him, I think at this point, unless there is some massive character development, I'd be pretty disappointed. He literally slaughtered the only other person she ever cared for, her only friend in the world, for a very very stupid reason. If he knew she was a dragon, he could have just talked to her about it, seeing as how they share a similar story. But noooo, kill everyone, and force the survivors to love you? Yeah, sounds like a plan.