In Slavic mythology, a rusalka is a female ghost, water nymph, succubus, or mermaid-like demon that dwelt in a waterway.
According to most traditions, the rusalki were fish-women, who lived at the bottom of rivers. In the middle of the night, they would walk out to the bank and dance in meadows. If they saw handsome men, they would fascinate them with songs and dancing, mesmerize them, then lead them away to the river floor to their death.
In most versions, the rusalka is an unquiet dead being, associated with the “unclean force”. According to Zelenin, people who die violently and before their time, such as young women who commit suicide because they have been jilted by their lovers, or unmarried women who are pregnant, must live out their designated time on earth as a spirit.
The ghostly version is the soul of a young woman who had died in or near a river or a lake and came back to haunt that waterway. This undead rusalka is not invariably malevolent, and will be allowed to die in peace if her death is avenged.
Rusalki can also come from unbaptized children, often those who
were born out of wedlock and drowned by their mothers for that reason. Baby rusalki supposedly wander the forest begging to be baptised so that they can have peace. They are not necessarily innocent, however, and can attack a human foolish enough to approach them.
While her primary dwelling place was the body of water in which she died, the rusalka could come out of the water at night, climb a tree, and sit there singing songs, sit on a dock and comb her hair, or join other rusalki in circle dances in the field.
Though in some versions of the myth, their eyes shine like green fire, others describe them with extremely pale and translucent skin, and no visible pupils. Her hair is sometimes depicted as green or golden, and often perpetually wet. The
Rusalka could not live long on dry land, but with her comb she was always safe, for it gave her the power to conjure water when she needed it. According to some legends, should the rusalka’s hair dry out, she will die.
Rusalki like to have men and children join in their games. They can do so by enticing men with their singing and then drowning
them, while the children were often lured with baskets of fruit. Men seduced by a rusalka could die in her arms, and in some versions hearing her laugh could also cause death.
Alternatively, they would attract men, mainly bachelors, and tickle them to death.