It’s an undead baby dragon, produced by a failed magical spell. It probably would be cute if it weren’t partially decayed.

Young dragons are relatively defenseless. They are born with relatively soft scales, which are shed and replaced with harder ones as the hatchling matures. Once a hatchling’s wings grow in, it typically marks the beginning of maturation. At this point they are often capable of hunting on their own and are usually left alone by their mother.

Not all dragons who die remain at rest—perhaps some dark mana permeates the soil of the clan's burial ground, or perhaps some spirits simply do not depart so easily. However it came to be, a very young Dorsal dragon fell to sickness, and the loss of a promising hatchling was mourned by all...and when the mourning faded, the rumors began. Hushed whispers told of a shambling, decaying thing of rotted hide and decaying sails, stumbling around in the depths of night. Rumors became sightings, and sightings became warnings. Most dragons will hear her approach—undeath grants neither grace nor speed, and one of her legs has all but rotted off—but a sound sleeper may find themselves awakened by the jaws of the dead clamping down on them.

It's probably a very good thing she died before her teeth grew in.