The Hairy Heart: A Guide to Wizards Who Won't Commit is a Wizarding self-help book, that topped bestseller lists. It is assumed that the book's purpose is to assist a witch or wizard to avoid having "a hairy heart," which is a Wizarding expression meaning to describe someone who is cold or unfeeling or who won't commit to a relationship. It should not be confused with Hairy Snout, Human Heart, a book about one man's struggle with lycanthropy.