In Finnish mythology, Näkki is a Nix (water spirit) residing in wells, docks, piers, under bridges that cross rivers, or murkey waters. It would pull young children into deep waters, similar to Peg Powler or Grindylow. It is also said the Nakki appears very beautiful from the ground, but it very hideous from behind. It is believed to be borrowed from the Näcken of Scandinavian mythology. Nakki is the also the name of a crater on the Jovian moon Callisto.