A/N: Originally I was planning this to be a one-shot, but apparently y'all like it! Yippee skip for me, I guess, so I'm expanding it into a two-shot. That's it, because I've got another full-length Undertale fic to finish, and don't give me Bambi eyes.
I said don't.
He should have been happy.
There should have been joy.
It only took a few resets, and nobody was dead. Everyone was saved.
Except Asriel...
But even that was an impossibility, wasn't it?
"But I've proven nothing to be impossible..." he whispered to himself in the darkness of his room. Small comfort.
"And that," he continued, "is the worst part of it. No matter how good of an ending I have, I'll never be satisfied. I'll always wonder, 'But what would happen if I'd killed X, spared Y, and never tried to be friends with Z?' Or, worse yet, what if I try to save Asriel, and can do so, but at the cost of everything else?"
That was the fiend that hid within the infinite possibilities that could still exist in the multiple timelines. Never would he be satisfied with what he had gained. Always he would be looking for another way, more possibilities, all on the foundation of a single, harmless-seeming question?
What if?
And then, an idea, one he'd never thought of, came to him.
"But there is another way," he whispered, and a grotesque grin distorted his face. "I wonder what will happen if I kill everyone? Not just a few, like I have before, but every single person, so there is nothing left? Not a single person would be left alive.
"Not one of them."
He heard his door slowly open. Breathing came in the darkness.
He heard Toriel place the plate next to his bed.
He heard footsteps as she turned and left the room.
He heard the gentle closing of the door.
And then he turned over in his bed, knowing that something had happened to his face, twisting it uncontrollably into an expression that was not his, and belonged to another person entirely.
And he did not care.
Somewhere in the darkness, there was laughter.
