In the early time of existence, there was neither chaos nor order, life nor death. Nothing new was created, for there was nothing to create from without destruction, and there was no growth, for there was no decay to spur it on. All was eternal, forever as it was when first born, and nothing changed. In short, shit was boring as all fuck, and something needed to be done. However, there were no higher entities yet to correct these errors of reality, and nothing new could be born from the stagnant realm. Then, another realm- which had long lain dormant- returned to life and activity. This realm was the True-Void, a realm of the purest energy, from which sprung the first eternals, the first interdimensionals, they were the law-makers and the law-keepers. These beings would become known as the first demons eventually, as from the template their creation from the energy provided, all demons (of the interdimensional variety) sprung forth. The first demons were the nine beasts and the entities known only as Darkness and Light, though it is unknown which group was born first. These eleven beings were the purest Demons, being made of almost completely pure demonic energy (refined only slightly to properly support consciousness and form), and were the most powerful demons to ever exist. Their roles in existence were quite different however, the nine beasts decided to fix realities flaws, give order and chaos, growth and decay, creation and destruction, and purity and corruption (the last being held by the first seven beasts, who patterned the seven deadly sins after themselves and their own personalities, providing corruption by which to gauge purity). On the other hand, Darkness and Light had no interest in helping reality, their only interest was in fighting one another, and that they did. Now, neither Darkness or Light were evil or good, just as the nine beasts were not evil or good, but they did appear as creatures which begat the idea that light was good and darkness evil, as Light appeared similar to an angel in most forms (or at least angelic) whereas Darkness was a shadowy mist in the form of a monster most times.
(skipping lines for the eventual continuation, for now, the truncated version of the end to the base story) Sepulchure left the nine beasts, allowing his power to act on its own so as to give himself the time to do his research. In his initial travels, he encounters a young demoness of great power who helps him in finding the source of demons (the void) and creating a method for which to access its power, thereby increasing both the strength and lifespan of the demon who would use the method in question. Eventually Sepulchure and the demoness (who was effectively his wife by this point) discover the method to access the void, and how to use its infinite energy to enhance oneself; however, the incredible amount of power which Sepulchure absorbed drove him completely insane, eliminating his mind and creating the entity which would come to be known as the God of Destruction. During this time, Light and Darkness's eternal duel has drawn to a close, with Light "killing" Darkness and scattering his soul across all of reality, hiding pieces inside of every demon to be born, interdimensional or not. This caused the demons to gain incredible power, but they needed to use certain methods to truly access it, this would come to be known in some universes as "Devil Trigger", while in some others, went entirely unnoticed.
(there is more, maybe enough to be referred to as much more, to this story, but for now this should do. I could probably write a full sized book about this stuff if I tried, and it probably wouldn't be that hard.)
