Keeper by Nia Farrell

Luke “Mad Dog” McLanahan and Isabella Castellari have a history. Kind of. He’s a member of the Avenging Angels MC and one of four brothers whom she thinks slept with her sister three years ago. Or did they? Nothing is as it seems. Isabella’s world is turned upside down when lies are exposed, truths revealed, and the man she’s been fantasizing about for three long years makes her an offer that she should refuse but can’t.
When Mad Dog finds Isabella stranded on a rural country road, remembering her toxic sister, he almost doesn’t stop. Seeing her as an end to a means, he brings her back to the Avenging Angels MC clubhouse and quickly learns that she’s different—very different—than what he expected. She’s a curious innocent, and willing to submit to his domination. But there are complications. A mob boss uncle, protective parents, a traitorous friend, and secrets that have been kept for far too long. Secrets that will either bind them together or tear them apart.