In the fiction of H. P. Lovecraft, a ghoul is a member of a nocturnal race that lives underground. Some ghouls were once human, but a diet of human corpses, and perhaps the tutelage of proper ghouls, changed them into horrific bestial humanoids. In the short story "Pickman's Model" (1927), the first of Lovecraft's ghoul stories, they are unutterably terrible monsters; however, in his earlier novella "The Dream-Quest of Unknown Kadath" (1926), the ghouls are somewhat less disturbing, even comical at times, and both helpful and loyal to the protagonist. Richard Upton Pickman, a noteworthy Boston painter who disappeared mysteriously in "Pickman's Model", appears as a ghoul himself in "Dream-Quest". Similar themes appear in "The Lurking Fear" (1922) and "The Rats in the Walls" (1924). Both of stories claim there are subterranean clans of degenerate, cannibals or carrion-eating humans.