Casbriel: An evil demon of the night who so hates the light that he refuses to manifest during the hours of the day. Casbriel serves the demon Buriel, who is described in the Ars Theurgia as a “wandering duke,” which is to say that, among the spirits associated with the points of the compass, Buriel and his company change their location and move however they please.
Casbriel is such a roguish and malevolent spirit that he and his compatriots are despised by all other spirits. Within his own hierarchy, he is popular enough that he commands eight hundred and eighty lesser spirits. When he manifests, Casbriel assumes a monstrous form. He appears as a massive serpent with a human head.