Origin
Very little is known about Ahmes. At some point he sought employment at the Wren Library at the University of Cambridge. There, he established himself as the curator of the Secret Wing, which houses occult and magical texts and objects, and became a mentor to Georgiana Snow
Creation
Ahmes was created by James Tynion IV, Ming Doyle, and Vanesa R Del Rey. He made his first appearance in Constantine: The Hellblazer #4.
Major Story Arcs
The Hellblazer
Working in the library at Cambridge, Ahmes twice encounters John Constantine, once when the man is drunkenly wandering the halls, and the next day when he returns seeking knowledge. He offers his assistance, which Constantine at first declines, and later helps Constantine locate a book on soul displacement. He explains the concept to Constantine.
Powers and Abilities
Ahmes is an immortal; whether this was achieved through some magical rite or spell, or is an inherent trait, is unknown. He has cultivated a vast store of knowledge on the occult and library maintenance. He appears to be capable of powerful magic, and to possess some level of clairvoyance or other unnatural knowledge of ongoing events.