Teogonia: Volume 2 by Tsukasa Tanimai

When Kai became the host vessel to the god of the valley, he was made a guardian bearer with power far beyond any ordinary human. To many, he is the embodiment of an ancient god known for its fearsome power and thirst for blood, and those seeking his protection have begun to form a small nation with the valley at its center.
To others, Kai is simply a poor young boy living in a remote village in the borderlands. A village whose existence is threatened by a hostile demi-human race that lurks in the nearby forest. It’s only a matter of time before Kai must fight to defend the village, but corrupt officials from the capital are driving the village to ruin before the battle even begins.
The mysterious priest, with magic far more advanced than his own, could be a valuable ally as Kai struggles to understand the human nation’s politics and the power of its gods. But with the priest watching Kai’s every move, his double life could soon be exposed.