Blood By Midnight by Cassie Alexander

Angela: Run. I need to run. My boyfriend, Mark, thinks his mafia connections will be able to kill my ex. But Gray’s an alpha werewolf and the leader of the Pack, Vegas’s most notorious motorcycle gang. It will take more than just a mobbed up human to take him down. To protect my boyfriend and my son—we have to run.
Jack: I’m the only one strong enough to save Angela—but even I can’t take on an entire werewolf gang. Which means I have to talk to Rosalie: the vampire who made me, the Mistress I despise. If I don’t, Angela and her son are as good as dead—so I’ll do it, even if swearing allegiance to Rosalie kills me. Again.

She’s a werewolf in danger.
He’s a vampire about to sell his soul.
Welcome to Dark Ink Tattoo, where needles aren’t the only things that bite.