He didn't see anything out of the ordinary. Maybe they were just as shocked as he was about finding a new reality?

Doubtful.

He only snapped out of it when he heard Frisk's worried voice over the tranquil rushing water. Looking down at her, he gave a soft smile and shrugged,"Just needed a change of scenery I guess. Don't much like to be home when it's so quiet."

He didn't want her to worry over something like this, it was unwanted and unneeded stress that he wouldn't give her.

Besides, it could have all just been a sleep deprived hallucination.

"W-ow bro, miiight wanna w-w-work on your ly-lying there. E-ev-even I was-s-n't sold ooooon it-t."

Sans froze for a moment before looking around for the owner of the broken and deformed voice, but was met with absolutely nothing. He held on to Frisk a bit tighter as a chill spread up his spine and coursed through his very soul.

They had followed him.

His eye glowed as he kept looking for whoever it was, but no one appeared. Even so, he didn't let down his guard.

It wasn't until a low chuckle souned right behind him that Sans freaked out. All in a the span of two seconds, he was on his feet and leaping away as he fired a gaster at the spot, leaving a smoking crater where he and Frisk had once been. No one had ever snuck up on him before, and he quickly decided that he didn't like the feeling. Maybe he should keep that in mind when he did that to others.

Laughter echoed around them, distorted and cut out, but it served to send another chill up Sans' spine.

He glanced down at Frisk for only a moment before returning his gaze to looking for whoever it was. They had still yet to come out, and not having a face to put that creepy voice to was really starting to get under his skin(heh).