Anchancho are considered very dreaded malignant spirits. Their counterparts are the Ekkekko.
There is a legends recorded of these spirits by Obitas Poblette that both the Anchancho and Ekkekko were the children of a powerful prince, the Malleu of Chacamita; the Ekkekko by his legitimate wife, Curaj Mama, and the Anchancho by concubines.
The Anchancho are believed to be responsible for illness and disease, and are sometimes spoken of as if they are believed to be spirits of disease. It is considered that they can enter and take possession of people when the soul (Jukkui Ajayo) leaves the body as in sleep or owing to sudden fright and cause illness exhaustion, and death. Also, they possess the power of the evil eye by which they can charm a person, then enter their body, and the suck their heart’s blood causing death.
Twilight, particularly short in the Andes, is an especially dangerous time when special care must be taken to avoid the Anchancho. They also frequent solitary mountain places, particularly storms and they voices utter the sound similar to a braying ass. A.G.H.
Osborne, Harold. South American Mythology. “Library of the World’s Myths and Legends.” New York. Peter Bedrick Books. 1968, 1985. p. 80