[Prologue]
Two thousand years ago Kaguya gave humans chakra. Five decades later Kaguya was sealed into the moon. One thousand years ago the moon disappeared, replaced with a new one. One thousand years ago the sky changed. The old stars disappeared, replaced with new ones.
One thousand years ago humans made a mistake; they took no notice.
This sky is not new. This sky has moved around for eons, hopping from dimension to dimension creating new beings in its wake. These new beings are bound to their individual star. These beings are granted their own powers. These beings are contractors.
For those who managed to take notice to the change of the sky were branded insane. The sky did no such thing. The sky is the sky, it has been there since time and will continue for the rest of time.
One man however, took heed to the words. The sage himself. He sent his paths to investigate beyond territory known. He sent them west, he sent them east, to the north and south. For years the sage found nothing. Just when he had given up, one of his paths disappeared. The path that went west. The sage could not understand why his path had disappeared. The path had not died, it had not been captured, but had just vanished. He himself decided to go, to see what had happened. The sage traveled through scorching deserts that left him seeing hallucinations. He had waded through swamps and wetlands that left him cold and chaffed. He had climbed mountains that left his hands blistered and skinless. He had made it to a land beyond his own. He had made it to Hell's Gate.
He saw things that are not natural, phenomena that are not of this world. He had found a break in the rift. A break in time, space, and dimension. Then, he too, had disappeared, his remaining paths along with him.
The sage had one last coherent thought before he was lost. It was more of a realization; the path he sent east had found Heaven's Gate.
From that point on no human travelled farther than land known to them. No human knew what waited for them miles away. No human knew of the sage's findings. No human new of contractors.