"The redcap (or powrie) is a type of malevolent, murderous goblin found in folklore of the Anglo-Scottish border region. The redcap is said to inhabit ruined castles along the Anglo-Scottish border, especially those that were the scenes of tyranny or wicked deeds, and is known for soaking his cap in the blood of his victims. He is also known as Redcomb and Bloody Cap." Source - https://en.wikipedia.org/wiki/Redcap