The Book of the Staff — Eric R. Asher

A demon unleashed. An ally imprisoned. Zola risks a pact that could kill them all ...Zola Adannaya, necromancer and mentor to Damian Vesik, seeks an ancient artifact in order to save her student. Unfortunately, the only beings with the knowledge she needs are demons she trapped long ago.Traveling to a small town in southern Missouri, where one such demon was cursed to a mundane existence, Zola must convince the creature to cooperate. Negotiations with a demon are always treacherous and Zola finds herself on a quest she may never return from. Her only hope lies in Corydon, on a distant battlefield guarded by an Old God.If Zola fails to end a conflict centuries in the making, Vesik could pay the ultimate price—as could the world itself.