Once upon a time, there was Nothing, an entity that lacked intelligence. Out of it, other entities were slowly formed. Out of Nothing came Something, and Everything. Darkness, and Light, Time, and Space; all of it was formed out of Nothing.
After countless ages, lifeforms began to appear, and Life and Death were born. The fundamentals of the Universe all emerged and were known as Immortals. Whenever they descended on the world below, all lifeforms would bow and submit.
However, not all the Immortals were known. It was said that there were seven children born Immortals that could interfere with the rules of the world with just a thought - Fate, Life/Death, Yin/Yang, Time/Space, Light/Darkness and Nature. No one knew the identity of the last son, not even the other Immortals. Because of that, it soon became widely assumed that there were only six sons of Nothing amongst the lifeforms in the Universe.
However, eons into the Universe, when all lifeforms were prosperous, something extremely shocking happened. Patches of the Universe began to disappear without a trace. The existing lifeforms, who had all advanced far in technology and magic and could roam the stars without a problem were being swallowed into thin air without a trace.
It wasn't long until the six Immortals noticed this, but it was already too late. By now, the number of existing lifeforms were so little it was negligible. The six sons of Nothing converged together and sought a countermeasure. After thorough investigation, they deduced that the lifeforms they had the most contact with were the first to disappear, and the remaining ones were the usually neglected, so they decided to avoid contact with these beings and observe silently.
Eons passed, and these fickle creatures managed to survive extinction. However, they were on the brink of destroying themselves. A war between the two strongest races had broken out over a thousand years ago, and it was reaching a precipice where either side was about to go extinct.
The Immortals were contemplating whether or not to interfere when a drastic change happened. Out of one of the two races, a supreme figure emerged. In just a hundred years, he grew from a little boy into a mighty commander that could swat the strongmen of his enemy like swatting a fly.
In a fit to end the war, he commanded legions and brought wrath upon the enemy stronghold, forcing the leftovers to flee to the ends of the world. Peace was established, and the era of the god race came. Kronos led the gods for a few millennia after conquering the daemon race before finally deciding to retire. He started up a peculiar little project he called 'humans'.
Millennia later, Kronos disappeared. Some say he went to search for the remnants of the daemons to eradicate them, while some say he had died trying to grow his power. In truth, no one knew where he went. However, he had completed his project and let loose this new race he called humans into the world.
It wasn't long after Kronos disappeared that the daemon race started to show their face again, and this time they had come back stronger than ever. With the peaceful times the god race had been living in, they had grown fragile and weak, hence they were no match for the daemon race. The gods were pushed back until finally they had to retreat from the rest of the world and into their stronghold.
Humans had already flourished and taken over the rest of the world by now. There were also some of them who could stand up to the weaker daemons. However, the daemons had no eyes for these weak creatures and also retreated to create a new stronghold on the opposite side of the world. Humans became the barrier separating the gods from the demons.