After clearing Frisk and Peace Line, the barrier was opened. The monsters who had been trapped underground for many years finally saw the sunset for the first time, and came to the surface to start a new and happy life. Because they left in such a hurry, the monsters more or less forgot something underground, and Sans was one of them.
This lazy man should have stayed at home and fished, but because his brother, Papyrus, had been urging him to pack up the things he forgot underground recently, he took a shortcut and came to the underground world.
The once lively Snow Town is now deserted and silent, with only the sound of "puff, puff" made by the snow on the ground being stepped on.
Things in the cabin were still messy, so Sans quickly packed up his things and prepared to teleport back to his new home. As a result, he noticed that the pet rock on the table had not been taken away, so Sans put it into his blue coat bag. Several cracks appeared on the stone, and gravel particles slowly fell from it. But instead of noticing, Sans took a shortcut back home...
(This is my first time writing an AU. The naming and plot may be a bit bad, and the settings may be lost as soon as I write them down. Welcome everyone to help point out mistakes! I hope there are no similarities qwq.
Note: UNDERSEAL means under seal. )
Concept: origin and end, redemption or destruction?