idk if this counts as horror but my favorite urban legend:
The Kunekune is said to resemble a slender, white humanoid shape, like a paper mannequin or a piece of fine fabric. It is said that the being can be found at lunchtime during hot summer days. The Kunekune lingers in widely extended rice fields or acres, in rare cases it might be found over the open sea. Its limbs are said to wiggle permanently, as if there was a straight gust of wind, even if it was a windless day. This behaviour gave the being the Japanese name "Kunekune", meaning "to twist", "to wiggle" or "to meander".
The Kunekune allegedly can only become visible from a distance; witnesses may see field workers or others closer to a Kunekune who do not seem to be aware of it. In some variations, if an individual tries to look at it up close, they will go insane. In other versions, if someone touches it, or simply comes too close, the Kunekune will kill them. Even looking at it from a distance for too long is said to be unwise. If someone does not approach or make contact with the Kunekune, it is said that the Kunekune will ignore them.