Miss White And The Seventh Heir by Jennifer Faye

Hardworking magazine editor Sage White's just getting used to being in charge, so she's alarmed to find sparks flying with her new assistant – the distractingly handsome Trey! Working together, they grow closer – but can their blossoming relationship survive when Sage learns that Trey is really Quentin Rousseau, seventh heir to the publishing empire – and her boss!