Goetia – S. L. MacGregor Mathers (1904) (quoted)
The Fifty-eighth Spirit is Amy, or Avnas. He is a Great President, and appeareth at first in the Form of a Flaming Fire; but after a while he putteth on the Shape of a Man. His office is to make one Wonderful Knowing in Astrology and all the Liberal Sciences. He giveth Good Familiars, and can bewray Treasure that is kept by Spirits. He governeth 36 Legions of Spirits, and his Seal is this, etc.
Amy appears as that of a humanoid of pure flame and inferno. He can make one marvelously knowledgeable in astrology, and as well in all the liberal sciences. He conjures excellent familiars. He can also thieve treasures preserved by spirits. He has a government of thirty-six legions. Amy is partially of the order of angels, and partly of potestats. It is Amy’s hope that after twelve hundred years he can return to the seventh throne: this of course is not possible.

Very little is known about the Demon Amy. When we’re able to find more information we’ll update here.