Monsters and Humans

A human goes looking for their younger sibling Chara but find themselves stuck underground with real life monsters! They were scared but soon found not all of the monsters in the unground are evil. They especially become fond of two skeleton brothers. One a little more then the other. They learn they want to free the monsters.
Little did they know their determination was more powerful then Charas. So they now bare the power to reset and save.
Will they use it for good or evil? Will they free the monsters or will they do what the others did before them and abuse the power?