The protagonist of Demonbane, Kurou Daijuuuji is a financially poor detective and former secret division student of Miskatonic University. He's hired by the Hadou Financial Group to hunt for the most powerful Grimoire. In his search, he comes face to face with a grimoire himself named Al Azif. In a fit of desperation, Al creates a pact between the two, choosing Kurou as her sorcerer. He discovers that she is the original Necronomicon he was looking for. Kurou becomes incredibly powerful when he uses Al's magic, allowing him to pilot the Dues Machina, Demonbane. Kurou's name is the Japanese romanization equivalent of the name Titus Crow, the main character in a set of horror fiction novels written by Brian Lumley.

(source: Wikipedia)