In Greek mythology as far as i can tell so far daimons are created from souls from the golden age.

Daimons in Greek mythology are usually in between gods and mortals when it comes to power. But the gods have also been called daimons before.

Anyway a possible way deterioration was created was that souls from past era’s were turned into a parasitic like form with little intelligence. That could also possibly mean the bloodlines from past era’s may have influenced charon and filthloid development as well possibly.

Also an additional lead from greek mythology that will be looked into but will probably come up empty handed or with info that needs to be pieced together.

Counterpart names from greek myth

Berinca = bai

Mors = chronos

Vita = Ananke

Only these three since they are the only ones that could possibly make it to another era.