Atonement for Buddha and Demon

[Waste wood flow + no system + time travel] In the glorious age, there were many geniuses, and without the intrusion of external enemies, evil thoughts arose within the human race and turned into evil spirits in the world, causing chaos in all directions. A person who does not belong to this world, ignores the shackles of the world, and gradually becomes a legend of the end of the era. One person and one beast meet in a remote place. The two of them each have hopes and grow together.