Skogsra are forest spirits found in Scandinavian folklore. Creatures that are female in appearance (at least from the front) and are well known for leading men astray.
Their appearance can change depending on who’s telling the story, consistently through the Skogsra looks like a beautiful woman when seen from the front, from behind she can either have a tail or some say she appears like an old hollow tree.
They can be good or evil, there are stories of them leading people, particularly men, astray in the woods, letting them become lost and never returning. But there are also stories of them favouring hunters and allowing them to experience unprecedented success while hunting.
These whimsical creatures seem to change with the wind.
They have appeared in modern culture in films and books, perhaps most recently in the film Thale. Where two men who run a crime scene cleaning business find a mute girl with a cows tail hidden in the basement of a house they are cleaning. Throughout the film, they learn about her captivity and situation. Towards the end of the film, the authorities (in the form of soldiers) become involved and Thale must escape with the help of the forest. It’s a pretty good film, I certainly enjoyed it as I was not overly familiar with the mythology behind it until researching afterwards. I’d certainly recommend giving it a watch.