A strzyga is a Polish owl vampire. You get them when someone is born with two souls.
This image is something I made for my vampire: dark ages game, it is why there is a separate lightly censored version of the image. My character had developed a necromancy ritual that creates a Strzyga as a reaction to the creation of the gargoyle. In the ritual she involves the Underworld hence the faint glagolitic writing on the flesh. In my eye it invokes a sense of old but also hints to the creature being ritual born. Yes the text actually says something though it is very fragmented due to the nature of how I placed it. I had the text bit written out in latin-script Polish then converted to the best of my ability. To briefly summarize; a spirit is invoked, as well as the name Marzanna, to inhabit the body so it can serve the purpose of Death.