The Raiapu Enga believe in a variety of supernatural beings, although anthropologist Richard Feachem states that the Raiapu "derive no joy or comfort from their religious beliefs" due to the pervasively indifferent or malevolent nature of those spirits. The "yalyakali", or "sky people," are fair-skinned and beautiful deities whose idyllic lives in the clouds mirror the agricultural and clan structure of the Raiapu below but lack the sadness of ordinary life. They are considered remote and unapproachable by humans. Feachem states that "the remaining spirit beings (ghosts and demons) are an aggressive and bellicose group who are mercilessly engaged in an endless cycle of revenge and mischief." The "yuumi nenge", or "destructive ground force," are ghosts which cause deaths from exposure in the forest. A "timongo" is a spirit which leaves a human body upon death and wanders the forests as "a source of continual fear and alarm for the living," particularly the still-living members of their own immediate families, against whom they bear "bitter grievances." Also living in the wild forests, as well as caves and pools, are evil, carnivorous demons known as "pututuli", which can change their shape but are often seen as being extremely tall with two-fingered claws. The Raiapu believe that human babies are occasionally switched by female demons with "pututuli" babies. "Topoli" are human sorcerers who possess secret knowledge of spells or other esoteric knowledge, and can defend against and communicate with hostile spirits. They "may be described as a healer of broken limbs, or a catcher of lost ghosts," writes Feachem.