Jarrod and the Demon’s Knight - Jarrod, #1

The wizard, known simply as Jarrod, has been living covertly amongst humans for over a decade. As a Professor at the University of Magic on his own planet, Prushal, he is ostensibly on Earth to research humanity's ancient magic. But the university's council no longer trust his motives and want him back. Jarrod's peaceful guise as an expert in historical artefacts is shattered as he becomes embroiled in a series of gruesome demonic murders where he becomes the prime suspect.
With pressure mounting, he doesn't have much time to confront the demon's knight, and clear his name. An unlikely alliance forms between Jarrod and Detective Widcombe as she and the wizard work to uncover the real murderer and the evil he is unleashing on mankind.