I should hate you - but I don't. Gem Haven MC series, #1

In Gem Haven, life comes with its own rules. Zane is just trying to make it through another day, holding the motorcycle club together piece by piece. But when his father, locked behind bars, asks him and his brother Kingsley for a favor-protecting two young girls in the treacherous world of foster care-they can't say no. Zane protects River from a distance, checking in on her periodically as she gets shuffled from one foster home to another through the years.
But at seventeen, she wants out. Zane steals her away and brings her to the compound, hiding her from the state. Her sister isn't as lucky and slips between the cracks. In the lawless world of bikers, River clings to promises and the soul-consuming desire to uncover the truth. As she fights to break through the walls guarding Zane's heart, she risks losing her own. He lives a lie, wanting what he can't have, playing someone else's game.
And the one person he doesn't want to hurt can never discover his secret.