I've mostly done all the rambling I had wanted to, but oh well. Yeah, Kaiba can get along with Aoshi but anyone else will have to hit him a few times before he stops growling. He and Roy would respect each other... after they fought themselves out. (Not that there's a parallel to Ed there, not at all.)

Aoshi is a warrior, and Kaiba can accept that. They'd make sense to each other on that level, I think - comfortable with the distance and the silence.

Like I said - Roy and Aoshi were my favorite, and I still feel like I didn't do it justice. Then again, that might just be Roy - he definitely has a sense of "Is this all I can do?" to him, there.