Beautiful Vengeance (previously published as Forbidden Promises)

The New York Times bestselling author of Neon Gods heats up the page in this spicy, dark mafia romance where a man out for vengeance falls in love with the daughter of his mortal enemy.
  Some lines should never be crossed . . . not even for love.   Sloan O'Malley just left her entire world behind—her family, her wealth, and even her real name. For the first time in her life, she's free. She can live the "normal" life she's always wanted: A life without fear. But there's nothing safe about her intensely sexy next-door neighbor.   Jude MacNamara has no room for innocence in his life. Only revenge. Still, he's never been able to walk away from the forbidden, and Sloan--who is every inch of pure, mouthwatering temptation--has forbidden written all over her. Only after it's way too late does he discover the real danger: claiming Sloan as his puts a target on her back. To protect her, Jude is willing risk everything . . . and to hell with the consequences.     Previous books in the O'Malley series:
THE MARRIAGE CONTRACT
THE WEDDING PACT
AN INDECENT PROPOSAL