Eames actually stops at that and turns to look at Arthur, completely baffled as to how to reply to that. He's certainly never thought about it, because whether or not you consider someone a friend isn't typically a complicated question. He supposes he'd be a little upset if Arthur died, but he'd also be a bit upset if Judi Dench died and he's never even met her.

"I don't know," Eames sighs, thoroughly exhausted like he always seems to be after dealing with Arthur, "but it's also not a question I really have the luxury of considering right now."