Sun & Blood by Crystal Frost

In a world of wolven, being average can get you killed.

Without a wolf spirit of her own, Violet Draven is basically a souped-up human and an easy target. When her twin brother Jax makes enemies with the future alpha from a neighboring clan, she tries to stop him. A concussion sends her to the Sentinel Clan’s doctor where the results of her recent tests reveal more than she bargained for. Determined to prove her worth, Violet trains with the best in the clan, but she’s still considered a liability. To protect her, Jax orders his best friend to guard Violet, making the fight against her forbidden feelings for her new bodyguard even harder to hide
Meanwhile, retaining control over his wolf is vital if Patrick Cowen is going to keep his past a secret. After losing his family more than three years ago, Patrick found a home in Sentinel Clan and worries about what will happen if anyone gets too close to him. Holding everyone at arms-length is the only way he knows how to protect his new family, but his eighteenth birthday, and first shift, draw near, testing his tenuous control. His combative wolf spirit won’t go down without a fight and if Patrick fails, everything he cares for will be lost. Driven by blood lust and the desire for power; rogue, red-eyed wolven begin attacking the clans. Their savagery knows no bounds. They have only one rule.
Submit or die.