Nocturnal Harmony: Nocturnal Alliance, Prequel 1 - Nocturnal Alliance, #1.5

Sabotaged and betrayed, once successful lawyer, Barron, finds himself contractually enslaved as an incubus to his ruthless rival, Kate Henshaw. Starved of the energy he needs, Barron spends thirty years as a tool to build Kate's empire. Strange things happen to Ava all the time, but tripping over a drop-dead gorgeous incubus in the park is no laughing matter. Barron's enthralling essence is both delightful and dangerous.
Thank goodness Ava and her Ace bestie, Trinity, are immune to his charm. Feeling hope for the first time in decades, Barron takes his first steps toward happiness, but Kate is a deadly adversary and the demon that turned him into a plaything isn't done with him just yet. To be free of both, Barron needs to find a loophole to get him out of his hellish pact. Nocturnal Serenade is a STAND ALONE book intended for mature readers.