Sans doesn't react further. He's always had a hell of a poker face. If you only give people the bare minimum and do your level best not to let anything bother you, then no one ends up knowing what parts of you to pick at. It's infinitely safer that way.

The question is interesting, or at least Bill's tone is interesting, like he's genuinely not sure. Like he genuinely doesn't know. Used to knowing how things will play out, isn't he? Used to moving the pieces around on the board himself, planning for every eventuality.

The universe has ways of throwing that type for a real loop. Or at least Wonderland does.

"heh."

He's about to say more than that, but then the world flips.

He's been through this song and dance before. He knows a certain someone who liked to mess around in his head with shit like this, changing orientations, changing perspectives, changing--values, in a sense. The world shifts on its Y-axis, and it's like that tug of blue, the feeling of gravity switching its direction.

Still, Sans isn't very good at being startled. It takes him a second, and his eyesockets widen as he tumbles a few feet toward the ceiling. But it's a dream, either way, and this is no different than being blue. So halfway there, he just teleports and lands easily on the ceiling.

He looks around.

"...man. looks like it's been awhile since grillby cleaned up the cobwebs."