Undergrim

long ago....
two races ruled over earth....

the MONSTERS ...and HUMANS.
they were in peace until they had a disagreement over land and fell into the war.
during the battle, the queen, TORIEL died...
The MONSTERS lost the battle cause of the death of the queen, and 7 of the HUMANS greatest magicians
sealed the monsters into the underground, never to be seen for a long long long time...
MONSTERS, raged over this and demanded a new law....
After a great battle with disagreement, the king, ASGORE, finely assented to the new law.. And so then, all humans that enter the underground shall be slayed..

But many, many years later...

a HUMAN, named frisk, fell into the underground. They had a great journey ahead of them..
The MONSTERS tried to kill the human, but only to be forgiven by the human and spared. But that soon ended when frisk killed a MONSTER.. And crossed the barrier..which leads into the monsters losing hope. The king, defeated and betrayed, felt a small slim of hope of all monsters being freed, just one last human..