Rusalki are river-dwelling cousins of dryads. They are sometimes called vilas although the latter are more closely associated with hills and forests. They have long, usually light-colored hair which they adorn with wreaths of flowers. They often wear sheer, flowing robes but they can also appear completely nude. Though usually silent, they are able to sing beautifully. They come out of the water at night to dance in moonlight.
They are said to lure men with their beautiful songs and then drown them. Other tales tell of them dancing men to the point of exhaustion and death.In the short story "A Grain of Truth" Geralt initially believes Vereena is a rusalka. Upon finally meeting her, he comments:
"You're so like a rusalka that you could deceive anyone. All the more as you're a rare bird, black-haired one."
- - pg. 80, The Last Wish (US edition)
- People sometimes mistake a bruxa for a rusalka.
- Naiads resemble rusalkas as they appear in Jarosław Musiał's illustrations.
- In Murky Waters, a peasant by the river will say: "Stay away from our Rusalkas" though there are none to be seen in the game.
- Also in Murky Waters, a peasant at the Country Inn will say: "I beg you, spare any rusalka you catch at the lake". When Geralt asks why, he will say "Well... quite useful creatures... comely... one shouldn't kill them...". Geralt responds that he has nothing to fear since he does not kill rusalkas or naiads.