Mettaton wanted to say that he didn't mind the designation. It was a fair trade for what he'd gotten out of it, maybe even skewed to his favor. But...Toriel was still right. He didn't wan to argue with her.

"I'm sure we will be able to fix this. I have much faith in Alphys and her abilities. I just...need to find my body.

If there's anything left of it. But there must be, it doesn't--ah. It's made of metal."

He almost said 'it doesn't turn to dust,' but quickly thought better of it.