The Hunter, Grayleer

Shotgun in hand, Michael Grayleer, a Hunter, scours the edges of the light tracking down all manner of wicked creatures, and eliminating the threats. But these days, evil is not so easily vanquished.
Haunted by his past conquests, Grayleer is on a mission of revenge. But evil is after him—attack after attack, each setback sends him careening toward the biggest threat he has encountered so far.
As he and his companions slowly lose themselves in the ruthlessness of their duties, Grayleer is forced to wonder whether his hunt is just—or even forgivable.
His choices: certain death or protection at the hands of creatures he would have put down in the past.