Forma Rot
Forma Rot is a mysterious neurological disease which seems to afflict residents of the Manifold Sky who exhibit a certain combination of intelligence, curiosity, and interest in the occult. It's origins are, as of yet, unknown.
Transmission & Vectors
The exact means by which an individual comes to be afflicted by forma rot remains unknown, though there is speculation that it might be a culture-bound (unique to academic and religious circles) variant of other forms of progressive dementia. Indeed, it appears that exposure to esotericist religious beliefs (i.e. Rostran Esotericism and its sects or the Eyes of the Void) raises the risk of forma rot, as more Rostrans of that persuasion are affected than other species, with particularly intense religious experiences often reported to be the immediate prequels to cases of forma rot in the participants.
Symptoms
Individuals afflicted with forma rot begin to show the stereotypical signs of neurodegenerative dementia disorders - such as Alzheimer's disease - including irritability, forgetfulness, confusion (especially upon waking), increased risk of falling, and a gradual loss of the ability to live independently. What distinguishes forma rot from normal senility, however, is that these symptoms can appear in patients of any age, and there is a notable degree of depersonalization and dissociative hallucination as the disease progresses.
Over time, the sufferer specifically begins to forget that they are different from people, places, and things in their environment, beginning to refer to themselves in the third person before eschewing personal pronouns and connections altogether. For example, if the sufferer's leg is infected, instead of saying something like "my leg is throbbing and painful," they might say "this leg looks irritated." During this latter period, any blood or body fluids originating from the patient take on a blackish hue. For unknown reasons, all creatures with a nervous system appear to instinctively recoil from these fluids, making treatment difficult as even doctors must fight their urge to step away.
Prognosis
There is, as of yet, no known treatment for forma rot. The sufferer will inevitably die over the course of up to one year, during which they will undergo what appears to be a rapid aging process. The bodies of forma rot victims decay extraordinarily quickly at all, with complete liquefaction occuring within one week and most skeletal remains crumbling to dust within a year.
Epidemiology
Forma rot is rare in the extreme, with scarcely more than two dozen victims attested to in the entire recorded history of the Manifold Sky. Forma rot does not appear to have any kind of genetic or congenital origin. Though there is some evidence that the disease may appear in clusters, as the earliest Rostran victims appeared in pairs or groups of three within a single Esotericist congregation, the reasons behind these clusters remains undiscovered. It may be possible for forma rot to spread through close contact, but, as the black ichor which leaks from victims is repulsive in the extreme, this seems unlikely.
History
There were no cases of forma rot recorded before roughly the middle of the 9th millenia AR.
Cultural Reception
Among Rostrans, where the disease was first identified, the threat of forma rot has been used as a warning against going to deep into certain spiritual practices for at least a millenia. Rostran Esotericists who attempt to call upon the spirits of the recently (i.e. less than one solar year) deceased are said to risk the 'curse of dissolution,' as this disrupts the natural cycle of birth, life, death, and rebirth that every spirit must step through.
This leg looks irritated. That made me laugh. Super not funny, but still. I liked this. The way you take dementia and twist it to something specially reserved to those who dabble in the darker side of things is nicely done. I love the writing, as always. I'm curious where the "speak to the recently dead" concept came from in the world. Like who started this idea? What is it about the recently deceased that led them to believe it was higher risk? Well done good sir.
Thanks for the comments! The 'recently dead' part has to do with the fact that Rostran Esotericists are animists that believe that they can commune with or even bind the spirits of animals, objects, or their deceased ancestors to 'borrow' their better qualities. Really, there's more to it then that - something to do with how the broader rules of the multiverse work - but that's getting into spoilers territory. I'll probably have an article on that part of things later :)
Ooooooo I shall wait, then. Sounds exciting!