Ravenous is the Void: Wee, Wicked Whispers: Collected Short Stories 2007 - 2008 in Bloomington, MN

A special agent with a special job, he's the janitor of all the unhappy, unpleasant, bleeding places of the world. He'll clean up your messes and leave nary a living witness in the muck that remains. Man, woman and child, his conscience is absent, his drive is relentless, and his soul is a ravenous void.
Cyclic rates of cannon fire and napalm. Cluster bombs and poison gas. Ever the calm, cool professional, he feels nothing. He is nothing.