Boggart

A boggart is a creature in English folklore, either a household spirit or a malevolent genius loci (that is, a geographically-defined spirit) inhabiting fields, marshes, or other topographical features. Other names of this group include bug, bugbear, bogey, bogun, bogeyman, bogle, etc., presumably all derived from (or related to) Old English pūcel, and related to the Irish púca and the pwca or bwga of Welsh mythology.[1][2][3]

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 evildoing, such as the abduction of children.