The Watch - The Ancients, #1

The mountain wilderness isn't a place for the meek. After decades of service to the Path he thought he had seen it all. But when a girl appears with the caravan under his protection, William finds that the Path always has more surprises and the girl is only the start of it. For the Path has a mission for him and the girl is the key to completing it. An old enemy dogs his steps as he guides the girl through her first steps along the Path, teaching her what he can while protecting her from the Darkness beyond the Path.
The same Darkness that chooses this time to rise against them, championed by a new enemy. For there is nothing the Darkness desires more than to corrupt the soul of a new Ancient. Especially when that Ancient has the potential to become far more than what she seems.