The Return / Jennifer L. Armentrout.

"From the New York Times bestselling author of the Covenant and Lux series comes a novel of danger, Gods and Titans...and an electric love story which will send you reeling. A year ago, Seth made a deal with the gods - and pledged his life to them. Now, Apollo has a task for Seth: one which sees him playing protector over a beautiful, feisty girl who's strictly off-limits. And for someone who has a problem with restraint, this assignment might be Seth's most challenging yet. Josie has no idea what this crazy hot guy's deal is, but he arrives in her life just as everything she's ever known is turned upside down. Either she's going insane, or a nightmare straight out of ancient myth is heading her way. Josie can't decide which is more dangerous: an angry Titan seeking vengeance? Or the golden-eyed, secretive Seth - and the white-hot attraction developing between them..." (publisher).