The most prolific female serial killer of all time... we think. Elizabeth Bathory liked to play with her food before she ate it. What began with severe beatings to her servants led to a very dark road into the occult and human sacrifice. She would seek out torture devices in Venice that allowed her to extract the most blood possible from a body in her lust to drink and bathe in it. Savouring every drip. Torture methods included starvation, mutilation, star-kicking, the iron maiden, and skin peeling.
Stories passed on through the generations claimed that she tortured and killed exactly 650 female victims. This was all written down in a book- but that book was never found.
I think it's safe to say, Bathory was a sociopath.