Ok, massive spoilers for Scarlet Hollow chapter 4 onward.
So we know that Reese’s real disorder is his ability to transform into his more supernatural form - a transformation that seems to be largely involuntary. This transformation might be powered by emotion - we know that the first time he transformed, he was able to revert back when he saw that his mother was terrified of him. Later in the game, should the MC take Reese as their lover, Reese will assume a more human-like form for most of the conversation outside the estate, but when he goes to attack Tabitha/Derekson, he becomes more reptilian. This implies that once he’s already assumed an inhuman form, he can willingly become more inhuman when he’s feeling aggressive. However, this shift into/within his monstrous form isn’t entirely intentional - while he’s already feeling amped up when he has his great metamorphosis in the clinic, he’s also very reasonably angry, considering that he’s just learned that his mother has been poisoning him for the last decade. The anger is human - and while his transformation ostensibly occurs because he’s skipped his daily dose of ricin, he notably gets more and more emotional as his transformation continues. Alongside everything else, this suggests a two-way relationship between Reese’s emotions and his relative humanity/monstrosity at any given time. That is, emotions can prompt his transformation, and can push him into more monstrous iterations of himself (relative to the form he assumes for most of chapter 5, where he’s largely human if you ignore the tail, talons, and ears), but when his transformation takes place, his emotions are massively exaggerated. This would explain why he gets much, much more impulsive in chapter 5 – his anger at the prospect of the MC being locked up as he once was is a very rational, human anger, but his inhuman transformation concentrates his rage into something more potent.
So, we have three potential causes for any of Reese’s symptoms at any time: his baseline chronic illness (if it exists), his ability to transform, and the effects of ricin poisoning. Reese’s symptoms, as we know, are as follows:
DERMATOLOGICAL AND MUSCULOSKELETAL
Joint instability (this guy can unhinge his own jaw for fun)
Horrible itching sensations + a sense of something crawling under his skin
Unusually long limbs and fingers (Marranos habitus)
Digestive sensitivities (note: these don’t stop him from eating people)
Probable nausea and vomiting
Immunosuppression (note: as much as this seems to be exaggerated or fabricated by Dr Kelly, it’d be incredibly inconvenient for her to say Reese is immunocompromised if he isn’t. After all, he could be plausibly VERY chronically ill without immune issues, enough so that seeing friends would be an issue. It could be fabricated, but possibly not)
if the immunosuppression is real, chronic respiratory infections. (If not, the respiratory symptoms belong elsewhere)
Exaggerated healing (this is probably explained by the transformation)
Chronic fatigue (probably explained by being poisoned)
Manic episodes (while his hyper-energised state might be a feature of transformation, the devs have confirmed that he was manic in the basement scene. This also might explain his disinhibited behaviour - mania does not make people dangerous or cruel, but if he’s unusually impulsive after having manic symptoms, that’d check out)
Probable depression (could easily be explained by circumstances, but if he also experiences mania separate to his transformations, we can’t rule this out)
Hallucinations? (These might not be hallucinations, and instead be ‘gaslit kid tries to explain his weird inexplicable memories to himself’)
Of these symptoms, the ones best explained by ricin poisoning would be GI distress and possibly chronic fatigue/exhaustion from fighting off the poison. While ricin can cause respiratory upset, this is unlikely in cases where ricin is swallowed, rather than inhaled.
Meanwhile, Reese’s transformation capacity is probably responsible for his joint instability, pallor, and potentially even for his unusually long limbs + fingers. Skin hyper-elasticity, likewise, might be explained by the ability to transform, and skin itching could possibly result from his being confined to a human body when not transformed. However, these symptoms could still result in functional impairment when Reese isn’t transformed - joint instability, in particular, would render Reese more prone to dislocations, subluxations, muscle weakness and tightness, and chronic pain. While Reese’s beastly form grants him inhuman strength, meaning that weakness probably isn’t an issue, he would still have the potential issues of accidental dislocations and pain. Likewise, while skin hyper-elasticity, itching, and long limbs could all be part of his transformation capabilities, they would also be consistent with several real-life genetic disorders: namely, Marfan syndrome, Loeys-Dietz syndrome, and several variants of Ehlers-Danlos syndrome. These disorders don’t cleanly explain his remaining symptoms, so for now, we’ll set them aside.
Finally, a couple of symptoms remain unexplained. Reese’s mood states might be exaggerated by his transformation and his life circumstances, but he is pretty classically manic when he’s not sedated, which indicates the possibility of an underlying condition. Similarly, if Reese is immunocompromised, neither his transformation nor his years-long ricin diet would fully explain that. If he’s not immunocompromised, digested ricin still wouldn’t explain his respiratory problems.
The symptoms timeline is useful for some disambiguating of what is what. So, consider when Stella asks Dr Kelly if Reese still likes devilled eggs. The last time Stella cooked for Reese was a few years ago; she, Kaneeka, and Reese are probably no older than 26 (assuming Kaneeka was one or two years into grad school before returning to the Holler), and realistically, around 22-23 seems more likely (given that Kaneeka had not been able to begin/had barely started grad school). Meanwhile, Dr Kelly began giving Reese ricin at age 15. Prior to that, she’d given him Klonopin (clonazepam), which would’ve caused a main digestive issue of constipation (potentially leading to consequences like pain, nausea, and possibly gastroparesis). Ricin poisoning usually results in the opposite issues to clonazepam, as well as profuse vomiting. Presumably, the last time Stella cooked for Reese was after he’d begun taking ricin. If he’s supposedly developed a tolerance (hence his transformation-aided ability to survive lethal doses), his nausea shouldn’t be getting so much worse that he’d have lost the ability to eat eggs. The game implies that Reese’s nausea is ricin-related, as he digests his mother (and Derekson) when he’s off-meds, and manages to keep everything down except the bones. But given that Reese’s nausea is progressive, it’s possible that if he has an underlying chronic illness, he is, in fact, experiencing nausea as a symptom.
So, Reese’s chronic illness needs to explain his respiratory issues, as well as potentially nausea, psychiatric symptoms, and possible immunosuppression. Additionally, it may partly contribute to his itching and his connective tissue symptoms.
I don’t know enough about medicine to make an educated guess. My personal bet would be on Mixed Connective Tissue Disease (MCTD), which is conveniently difficult to diagnose. If he has the right antibodies, his hardened nails, respiratory issues, immune dysfunction (supposing he has some kind of leukopenia), and difficulties with food would all make sense. Psychiatric manifestations wouldn’t be out of the picture so long as psychiatric manifestations of lupus can appear in MCTD. Otherwise, I don’t have a good guess. His joint instability, stretchy skin, and marfanoid habitus all resemble hEDS, but while hEDS could create nausea, it wouldn’t explain immune or respiratory issues.
So, Reese’s final illness diagnosis depends on whether his respiratory and immune dysfunction are real or fabricated by Dr Kelly. If they’re real, I heavily suspect MCTD or a similar illness could be at play. If they’re fabricated, hEDS + a mood disorder could explain his symptoms.
