Cayros
Cayros: One of a number of demons named in the Ars Theurgia as chief dukes who serve the infernal prince Dorochiel. Cayros is a night-demon, bound to serve his master in the hours between midnight and dawn. He is tied to the hierarchy of the west. As a demon of rank, he has four hundred ministering spirits to carry out his wishes.
SOURCE:
The Dictionary of Demons written by Michelle Belanger