Lady of the Plucked Eye and Heart

The Lady of the Plucked Eye and Heart is an unseen being, presumably a fairy, who lives immured in the castle of the Plucked Eye and Heart and by magic entraps such sanguinary men as Henry Lascelles into believing themselves to be her 'champion'. Once consumed by this belief they are compelled to challenge all other men who approach the Castle, and unless swiftly placated (as one is by the wary and quick-witted John Childermass) they fight the intruder. The conflict can only be ended by death - and whoever kills the Lady's champion is then caught up in the spell and takes the place of the man he has killed.

Mr Norrell states that some fairies "delight in pain and death", and The Lady is presumably one of them[64].