Before anything existed upon the Earth, there were only two non-beings that emerged from the chaotic nothingness the universe was once composed of. One was light and the other was darkness.
Long before the mountains stood proudly before the village, before the rivers ran freely in their beds, before these autumn leaves fell upon the wind, and long before humans and shinobi walked the lands, there were only these two things that flowed together as one and dispersed into two.
There was no good or evil, just power. There was no purpose, thus there was nothing but the purity of either separately and the balance of both together.
One could not survive without the other and together they both clashed and embraced each other in infinite circles for eternities. Even now, they are intertwined, though they are hidden now.
But when they intersected, things came into existence; the trees, the earth, the wind, the seas, the skies, the shining foreheads of farmers and bloody swords of the warlords, the smiles of the children and the tears of the dying were all birthed from the union of light and darkness. They were brothers and sisters, parent and offspring. Love and hate, sacrifice and vengeance, victory and loss, laughter and silence all stemmed from the same origins of light and darkness.
Even you and I are made of such stuff.
Yet soon, Time was created from the same elements and it overtook light and darkness until the two were dissected and strewn about everywhere in the world. There are remnants of these life-giving components, as their duality spins the balance of existence, but Time sealed their most concentrated shards away in two beings that encapsulated both non-beings best.
One had eyes of pure white and the other had a matching pair of abyssal black.
They were the only vessels capable of holding in an infinity and a void so Time hid the light and the darkness within each of these two humans – no, they were not entirely humans as they were two halves of a whole that encompassed something entirely beyond the boundaries of the mortal plane. They were never to meet or to entwine with each other again, Time had determined, for if they were to ever reunite, there would inevitably be a collision.
When two great forces come into contact with each other, impact is a given. But light and darkness have already melded together multiple times, each respective clash resulting in the cataclysms of many things, shaking the world dangerously on its fragile roots. Their last creation was Fate, which bound many other things tightly together to keep the world from disappearing. And Fate was the one that frantically tied these vessels together despite Time's vehement attempts to separate the two.
It was always a push or pull between these two chosen vessels, like a tide waning back and forth because of the force and gravity of something greater than either of them.
But just as things pulled apart roughly promise to rejoin just as fiercely, light and darkness will surely reunite… with consequences unforeseen.