Ylemlys: According to occultist Mathers, the name of this demon means “the silent lion.” Ylemlys appears in connection with the Holy Guardian Angel working in the Sacred Magic of Abramelin the Mage.
He serves in the court of prince Ariton, one of the four demons said to rule the cardinal directions.
His name is alternately spelled Ilemlis.
SOURCE:
The Dictionary of Demons written by Michelle Belanger