You weren't fully awake when Sans appeared in the bedroom.
The room was dimly lit, so it took you a moment to realize it was him. He was practically a silhouette; the small pinpricks of light that made up his pupils were barely visible. He stood by the doorway, making no noises or movements.
You realized that it was possible that you were still dreaming. After all, you've had problems with sleep paralysis before. There wasn't a good reason for Sans to come into your room while you were sleeping, even if you kind of wanted him to.
Even if you had a thing for him.
He was still just standing there. He seemed to be watching you. Then, slowly, he started to make his way over to you.
Well, if this is just a dream, I hope it's a good one, you thought. You found yourself wondering what it would be like to kiss him, to press your lips against his mouth. Would you just be kissing his teeth? Was there any magic that would allow him to kiss you back? You had no idea.
He was standing right next to you now. He stood still for a few more moments, then, gradually, he knelt down next to you.
His face was right next to yours. His eyes seemed to burn holes in your heart.
It then occurred to you that this might not be a dream. That this might, in fact, be real. That he might actually be kneeling next to you, looking at you.
Your heart started pounding.
He leaned close to you. His hand came towards your face.
You had no idea what you would do if he actually kissed you. Kiss back? What would happen after that? What would it mean? I guess that doesn't matter now. You closed your eyes, and waited.
Several long, agonizing seconds passed.
Waiting…
…
Then you felt the tip of a marker on your face.
You smacked the marker out of his hand. It soared through the air and collided with a nearby wall, leaving a blue streak on impact.
You were awake.
"oh, hey, you're up," Sans said, grinning.