[That confusion gets a small chuckle out of Mettaton. He's pretty sure he's about to give her the fright of her life but, alas, that's just how it is.]

Destroy humanity. It's a rather embarrassing thing, really, and is not at all in my programming anymore, but the monsters that I come from originally were worried about humans and their frightening tenacity so... they made me! Of course I knew the moment I woke up that I was never meant to be a murderer of any kind, and promptly turned myself into the perfect entertainer for monsters and later humanity!