Faerie
Have you heard the horns of the Wild Hunt in the sky or seen things from other times pass by your very path? Well, you must be of the shee then. Those who are fae, can sense Fairie, a world parallel to this where time flows differently. In some places and on some days, the unreality of Faerie is more sensable than otherwise. Those scars of reality itself are dangerous to any shee, who lets themselves get seduced by them. When one falls into Faerie, one can spend mere minutes or days there and when one finds a way back centuries and even millennia can have passed.
If one sees the ghostly figures of Faerie walk around and one cannot fight the urge to follow them, then one always has to walk widdershins (counterclockwise) to their route, so that one does not loose oneself in Faerie. Those scars of reality that enable the entrance into faerie, are temporary each and will be over after a certain amount of time. Times like midsummer, Beltain, Samhain or midwinter are especially dangerous times, since Faerie is at its strongest there, making the urge to wander towards it even less resistible.
You are of the shee, yes? Then take heed, for this world is not yours, but Faerie is. You are a creature that should not be and reality despises you. Faerie, the world of unreality, wants to take you back, but you have to fight it to stay in Mereldia.
The Faerie kingdom is also referred to as TÃr na nÓg. While the gates to it have been closed, the cosmos cannot cope with the imbalance of the fae creatures in Mereldia. This is why the scars appear and try to pull one back. There are not many reports, but I have once been fortunate enough to meet a fellow púca who has claimed to be in Faerie twice, one before the closing of the gates and once after. He told me how once upon a time, it was hard to get back to Mereldia when one once was in TÃr na nÓg, but now that the gates have been closed, one lingers in the space of unreality until one can fight oneself free of it and return to the mortal land. There is no possibility anymore to get to the Faerie kingdom this way, but one still can be caught in the border of unreality. As the púca assured me, not a pleasant experience.