Since we literally just came up with this idea of defining characters as "Symbolic" a few moments ago with everyone's help, we don't have an exact definition written yet, but Symbolic characters will essentially be representations of the things I was mentioning earlier (Doubt, Madness, and now as you see, Death). Symbolic characters will be non-human, non-demon, non-animal and will likely have no gender.
As such, we plan to change the designation of Death and Hades (WA) from "Demon" to "Symbolic."
A full definition will be added to the REG along with other necessary entries upon the release of RoJ.