Neptune’s Judgment

Cain had spent three painstaking months concocting a specialized virus. He knew if the virus tried to use the woman's vitality to replicate, she would notice, so he altered the toxins that filled the Purgatory Volcanic Range so they would act as food for his creation.

With every breath the woman took and with every ounce of energy she channeled from this place, toxins entered her body. A Third Realm life form like the woman would normally have found such toxins trivial, so she did not even bother to spell them. Yet that was a grave mistake as it was constantly fed the replicating virus inside her, which became a blazing fire once activated. 

Of course, the flames erupting inside her were not powerful enough to truly kill someone of her level. Even exploding from within, they lacked the raw might necessary to end a Third Realm existence outright or cause any severe damage. But they didn't have to.