Stryzygis started out as regular humans; the only difference was that they had two souls and two hearts. They typically die at a young age, but only one of the hearts stops beating and only one soul leaves the body. The other heart continues to beat and the remaining soul survives, and that's when the human corpse returns as a strzyga, according to Meet the Slavs.
A strzyga's physical appearance resembles that of a normal person's, except for its blue-gray skin. Typically, it stayed indoors in abandoned places doing household chores or at graveyards sleeping during the daytime. At night, however, they went on the prowl to feed on humans, and on some occasions, animals too. Stryzygis' main source of food was human blood, but they also ate the organs of their victims, as reported by Lamus Dworski. According to lore, the longer a strzyga lived, the more drastic it changed in appearance. They were known to take the form of an owl, complete with feathers, claws, and beady eyes.
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