Mettaton is actually rendered speechless and wide-eyed for a moment. Did...did Kaworu just say he was sorry? Honestly and truthfully?

His usual tone of condescension wasn't present and...Mettaton doesn't know what to do. He had never believed he could relate to this guy, this emotionless, shitty not-human who looked like a human.

Maybe it's because he's already upset, or maybe it's because he never expected such a thing to leave Kaworu's lips. Hell, it could have been a mix of both. But either way, Mettaton shifts, slowly pushing himself to his feet. He moves like he's walking through a wall of water, but at least he's moving at all.

Once he's facing the young man, he simply looks at him. The expression he wears isn't quite pity. Just raw regret. For everything.

"It isn't a good feeling," he says quietly. Before either of them could really process it, he's hugging Kaworu. Selfish or not, he's doing this. It's weird to derive comfort from someone you usually held in contempt, but...Kaworu seemed to be able to understand.

That means something to Mettaton.

"I am sorry for how I addressed you when you came in. It was rude."