Blood kin - M. J Scott

In the second in M.J. Scott's popular fantasy series, a city where human and Fae magic rests uneasily next to Vampires is under great threat. A fragile peace between four races is beginning to falter and it is up to spy and thief Holly, a half-breed daughter of a Fae Lord, to restore the balance. Guy DuCaine, a Templar knight, is sworn to duty, honour and loyalty, all the things that Holly is not. But when treachery and violence threaten both of their worlds, learning to trust each other might be the only thing that can save them and their city.