Indeed. The fact proved that there were some dark creatures aside from the demons who didn't go into the neutral camp.
For example…the beastmen.
Most of them were dark creatures because their ancestors were animals who gained abilities from the demons to become humans.
People said that the beastmen should be the soldiers of the dark camp, but the majority of them held the position of a treasury.
They recorded a lot of dark camp's history, collected various important items and such.
This is why they were also close to the sacred beasts and monsters— because beasts and monsters protected them along with those important items.
There were also the giants who were included in the dark camp side.
They held the position of the dark camp's sword, just like the celestials being the light camp's sword.
What about the dwarf? They were in the light camp and they were the one who supplied weapons to the light camp.
