Boggart

In English folklore, a boggart (or bogart) is, depending on local or regional tradition, either a household spirit or a malevolent genius loci inhabiting fields, marshes or other topographical features. The household form causes mischief and things to disappear, milk to sour, and dogs to go lame. The boggarts inhabiting marshes or holes in the ground are often attributed more serious evil doing, such as the abduction of children.