In 1521, the Dominican inquisitor Silvestro Prierius published his De Strigimagarum, Demonumque Mirandis (On the Wonders of Witch-Magicians and Demons). According to him, demons were more than willing to commit acts against nature if it resulted in the sinning of witches. He referred to the confessions of female witches who admitted to having sex with demons with bifurcated penises (membro genitali bifurcato) such that they were penetrated both anally and vaginally simultaneously. With the Devil no longer restrained by ‘nature’, the emphasis on unorthodox sexual practices between witches and demons increased over the next century. Thus Henri Boguet wrote: ‘Satan couples with witches sometimes in the form of a black man, sometimes in that of some animal as a dog or a cat or a ram.’

Philip C. Almond, The Devil: A New Biography (2014)