Tlahuelpuchi, or colloquially Glowers, are a breed of Vampire native to the Mexican district of Tlaxcala. They are one of the few mortal breeds, gaining their powers around puberty, though they do live longer than normal humans. They are organized into small tribes which are usually led by female elders, the females being more numerous and powerful than the males.
Tlahuelpuchi can shapeshift into the form of a large bird, such as a turkey vulture. However, the illusion is not perfect, as the shapeshifted form gives off a colorful aura visible to anyone, even non-magical humans, and is thus easily distinguishable.
Tlahuelpuchi are fairly unique among Vampires, in that their condition is not transferable, and does not require the death of an individual. Rather, the population of that area seems to carry the vampiric condition as a recessive gene, which always appears in the child of two Tlahuelpuchi, and can occasionally appear in the child of two normal humans. The powers begin to develop around puberty.