Pestilence is a Curse that was born alongside The Exiled One as part of the Universal Law of the God. It is the Spirit that brought the demise to the race of Children and the spiritual father to all diseases and maladies that would travel the Universe. Despite being a Curse, Pestilence was resilient, powerful and did not require a host to survive, though the later is an assumption that it does not use The Exiled One as host.
When the Gods prepared for war against one another, Pestilence disappeared, reappearing when the Universe was split into Earthen and Ethereal. Shortly after, Pestilence took over the body of a Demon and became the embodiment of disease, as well as the very first Aspirant to exist.
To this very day, Pestilence preys upon any Being capable to withstand the diseases it is delivering to the worlds.