Fairy tales I made up.

Fate

"The Demon king was a ruthless, fearless, and unbeatable individual that resides in the north, ruling the demons and bearing the keys of the Doors of Hell. The immortal, invincible one who stood firmly against the Gods. 

The gods always fought to seal of the gates of hell and put an end to the demon race, and their arms and legs were the mortals. Once in every century, they would choose a mortal human and grant them their blessings. With the holy power, the hero would face the Demon king. For only a mortal's sword of honor could bring an immortal to sleep and become one with the nature. They would fall asleep in the embrace of mother earth for another millennia.  

But, the heroes always lost. For the Demon king was too powerful for them too destroy, and he was not humane, he did not bear any mercy. He would destroy anyone and everyone who dared to cross his path. But the mortals never feared, and nor did the heroes, because the gods are on their side, and victory will one day come to the righteous! And if we don't keep fighting, the Demon King will unleash the Doors of hell and destroy everything!

This century, you, my dear, have been chosen as the hero. You shall pick up the sword of honor, hone your skill, and fight to defeat the Demons! You, my dear, will finally bring us peace!"

The child grew up hearing this from the head priest. As an orphan, he had no other choice. He couldn't run away from his fate. Don't misunderstand, he was thankful to the temple for taking him in, raising him, feeding him. He was thankful to the gods for choosing him. He was proud of his powers. He was keen to protect the villagers he held dear. To him, who didn't have the warmth of a family, the whole village was hid family.

But, he sometimes couldn't help but feel wrong. It's true that sometimes portals would open up whenever and wherever, and monsters would pour out from hell, kill people, destroy villages. Holy knights would have to fight them off. And after some times, the portals would close themselves. But, he couldn't understand why the Demon lord would cause havoc like that. And, if he wanted, he could've destroyed the mortal kind in any moment. He simply had to keep the portals open for days, a month at most. So why, the boy wondered, is it that people are trying so hard to kill the one who is actually keeping them alive of his own will. Nobody seemed to notice, that despite their continuous cursing, the Demon king was showing them mercy. 

Nonetheless, the ten years old boy kept training. As years passed by and he turned eighteen, he set off to fight the King of hell. He had small but reliable company consisting a knight, a saint, a magician and shield bearer. 

They marched to north, and the closer they were to the gate, the better they realized how strong and merciless the north was. But they kept moving forward. The hero couldn't help but realize that their chance of winning was as low as the temperature. When they reached the Demon king's castle, the hero felt his legs trembling. But he kept repeating in his mind the words of the head priest, if he doesn't end the Demon lord, he will destroy everyone. The hero has to protect the civilization. So that the Demon king can't destroy the villagers.

It was all in vain. Fighting an immortal was impossible. The battle was short, and all of his  comrades fell one by one, leaving the hero as the only one standing.

"Haaaah....." The Demon king sighed. "How many times do i have to go through this? How many centuries before you mortals realize that it is impossible for you to defeat me?!" He brushed the jet black locks of hair off his forehead. "If you really want to defeat me, tell them to come down here, tell them to stop hiding in their safe heaven up there. I have been calm for many years, but it is about time my patience runs out."

"What.. do you mean?" The hero staggered. His vision was getting blurry, and it was becoming hard to breath. Despite, he kept his sword straight, pointing at the immortal.