Klabautermann

A Klabautermann (German: [klaˈbaʊtɐˌman] ) "hobgoblin"; or Kalfater ("caulker") is a water kobold in Frisian, German and Dutch folklore that assists sailors and fishermen on the North Sea in their duties. Dutch/Belgian tales of kaboutermanneken described them as cave dwellers in mountains, who may help out humans who put out offerings of bread and butter, sometimes out in the open, but other times at their millhouse or farmstead.