Powers greater than yourself, untouchable, unreasonable, have an incredible sway over your own destiny, directing its twists and turns without even an 'if you please'. Sans would have just one question for that:

So what else is new?

Tack that onto the lengthy list of things Sans doesn't dare lend his voice to, because for those who haven't figured that out yet, they should hang onto that blissful ignorance for as long as they possibly can. Because there's really only two ways it goes when one is faced with the utter futility of your own existence.

Personally, Sans would rather laugh than the alternative.

Sasuke's already desensitized, there's those that would argue this puts him at a distinct advantage for his age.

"Specist," retorts Sans, but by his grin, one might take that to be a joke. "Monsterkind's been around for millennia, but after burying us in the Underground, you humans forgot all about it and moved on," Sans says, shrugging easily, "But, eh. No hard feelings."

He eyes Sasuke off, appraising him.

"'Sides, who knows if you're even from--" Well, hey... not that Sans is any stranger to abruptly changing eye colors, or it's, uh, magical equivalent, but that's not something he thinks most humans can do. "Um..?"

There's a funny thing about this skeleton. He's got no marrow, but rather his whole being lights up with the only thing equivalent to Sasuke's chakra... magic. Compared with a human, there's just enough 'physicality' to be a solid, living thing, and all the rest is pure energy.

"Wow, buddy, take a picture, it lasts longer."