Women (rare: men) who possess supernatural power and usually come from a non-human world (from sky, from under the water, they are winged beings, bird- or animal-persons; rare: a girl of higher social status than the hero) take off their clothes (feather skins and the like) or part of it. Because a person hides the clothes (of one of them), their owner(s) have (has) to marry him or help him (rare: her)