The Immortal's Unrequited Bride

A love that endures beyond death itself. Ethan Kemp is a healer, not an assassin. But he's found an unexpected home in the Irish stronghold that houses the Assassin's Arcanum - men who will kill to protect their Druid brethren. Too bad there's a ghost that won't give him peace. Centuries in the grave, Isibéal Cannavan has longed to be reunited with her beloved. Finally, he's returned to her.
She'd recognize Lachlan anywhere, even as an American warlock called Ethan. But her path to reuniting with him in the land of the living runs through hell itself, and she'll have to take Ethan with her.