You are
pretty sure this disease was not described anywhere but in ancient sources originating from Azlant, where it was, like, exceedingly rare, and the causes were debated but deemed non-infectious. The effects of this disease would be roughly as follows and any magical cure should help. It does not heal on its own and the medicine to cure it was unknown in the ancient Azlant (maybe because there was no need to find one).
Quote:
A creature's skin and flesh transform into a clear, slimy membrane. The creature’s new flesh is soft and tender, reducing its Constitution score by 4 as long as the condition persists. If the creature’s flesh isn’t kept moist, it dries quickly and the creature takes 1d12 points of damage every 10 minutes. Remove disease and similar effects can restore an afflicted creature to normal.