Strzyga , Stryha is usually a female demon from Slavic mythology. It is somewhat similar to a vampire.
Origin
According to Aleksander Brückner, the word is derived from Strix, Latin for owl and probably the origin of the term Strigoi, a troubled soul of the dead risingfrom the grave in Romanian mythology. It is unclear how the word strzyga was adapted by the Polish people, though it might have been through the Balkan peoples. The term strzyga could also sometimes mean a vampire or upiór. After the 18th century, there was a distinction between strzyga and upiór; the first one was more connected to witchcraft, while the latter was more of a flying, vampiric creature.
Beliefs
A strzyga is a usually female demon somewhat similar to vampire in Slavic folklore. People who were born with two hearts and two souls, and two sets of teeth were believed to be strzygi. Somnambulics or people without armpit hair could also be seen as ones. Furthermore, a newborn child with already developed teeth was also believed to be one. When a person was identified as a strzyga, they were chased away from human dwelling places. During epidemics, people were getting buried alive, and those who managed to get out of their graves, often weak, ill and with mutilated hands, were said to be strzygi by others. It is said that strzygi usually died at a young age, but, according to belief, only one of their two souls would pass to the afterlife; the other soul was believed to cause the deceased strzyga to come back to life and prey upon other living beings. These undead creatures were believed to fly at night in a form of an owl and attack night-time travelers and people who had wandered off into the woods at night, sucking out their blood and eating their insides. Strzyga were also believed to be satisfied with animal blood, for a short period of time. According to the other sources, strzygi were believed not to harm people but to herald someone's imminent death. In this, they resemble Banshees.
Methods of protection
When a person believed to be a strzyga died, decapitating the corpse and burying the head separate from the rest of the body was believed to prevent the strzyga from rising from the dead; burying the body face down with a sickle around its head was believed to work as well. Other methods of protection from the strzyga included:
Burning the body
Hammering nails, stakes etc. into various parts of the strzyga's body