Imshael

"You offer me a stately dinner, when what I want is the ravening, bare-fisted gluttony of a starving man."

Imshael is an ancient demon, purportedly one of the first demons to come in contact with human Magi. Imshael itself identifies itself as a "spirit of choice" although it is more commonly known as one of The Forbidden Ones.

Background
"The first of the magus cast themselves deep in the Fade in search of answers and power, always power. They found the forbidden ones – Xebenkeck, Imshael, Gaxkang the Unbound, and The Formless One. Many conversations were had and much of the fabric of the world revealed. And thus the magic of blood was born."

- Unknown mage

Bugs

 * If the Inquisitor defeats Imshael, but leaves the keep without claiming it, Imshael will respawn, and will still present his offer to the Inquisition. It is thus possible to receive multiple Amulets of Power granting ability points to Cole and other loot which can be sold after defeating Imshael, as well as experience points, and then accept the offer as well.
 * This bug seem to have been solved with patch 2 (Imshael don't respawn - even if the player don't talk to Ser michel before going to the Keep).