The "birth of humanity" in this world actually hasn't lasted for long.
Even perhaps ten thousand years ago, the ancestors of humanity were still like other demon beasts, surviving in the forest as part of demon beast tribes. They were called "Ghost Demons," enjoyed living in groups, fighting collectively, and even liked making weapons and equipment from the skins and teeth of other demon beasts.
At some unknown point in the past, these tribes, similar to primitive people, gradually gathered and formed tribes. These "Ghost Demon Tribes" in turn attracted the covetous eyes of other demon beast groups, leading to many demon beasts, who either had conflicts with the Ghost Demon groups or didn't want to see their growth, joining this war.
This marked the first Demon Beast War.
Angels were born several hundred years after the first Demon Beast War.
