Florence de Grey is a character in the fourth book. She is a villain endowed with the powerful ability in oath-binding, thus in which she keeps several oaths dipped in poison in her bag. Once any of the oaths are broken, the person who broke them would suffer with pain. Florence and her husband Usher de Grey adopted Billy Raven when the Bloors asked them to. They live in the Passing House, in Crook’s Passage, further down Hangman’s Way into an alley. Florence is a woman of medium size with greying hair and glasses thin lenses. She gives Billy a room of his own with toys, books, his own TV and computer with his own four-poster bed. A cat named Clawdia lives in the passing house.