In English folklore an Asrai is a type of aquatic fairy, similar in some ways to mermaids, nixies, selkiess, sirens or morgens. Some sources describe them as timid and shy, standing only between two and four feet tall, while others depict them as tall and lithe. They are said to look like beautiful young maidens, sometimes as young as children, while actually being hundreds of years old. They may have webbed hands and feet, resembling some descriptions of selkies.
If an Asrai is seen by a man, her beauty is so great that, according to folklore, the man will instantly wish to capture her. The Asrai are as deathly afraid of capture as they are of the sun, because if captured or if a single ray of sunlight touches them, it is said that they die and turn into a pool of water. They are, however, said to enjoy bathing in the moonlight.
The tale told of one fisherman who caught an Asrai claims that the touch of her skin was so cold, that where the Asrai touched his arm while pleading for her freedom—and her life—the flesh has never been warm since.
Tales from Cheshire and Shropshire tell of a fisherman who capture an asrai and puts it in his boat. It appears to beg for freedom in an incomprehensible language. He covers it with wet weeds, and it continues to complain, its voice getting fainter and fainter. By the time he reaches the shore, it has turned to water.
Their inability to survive daylight is similar to that of the Scottish Fuath and the Germanic Dwarves. According to folklore the deeper Meres in Cheshire are said to have contained this life form in the past.