Aleasi
Aleasi: A night-demon in the hierarchy of the north. According to the Ars Theurgia, Aleasi serves the demon-king Raysiel and holds the rank of chief duke. He appears only during the hours of the night and is reputed to have a very obstinate and evil nature. Forty lesser spirits serve him, carrying out his commands.
SOURCE:
The Dictionary of Demons written by Michelle Belanger