Just Another Ranker - Bill Willingham - Bog

Johnny Underwood longed for a life of adventure, and he got his wish, beyond his wildest dreams. He was recruited into a modern mercenary rifle company that plied their martial trade in a world of warrior-zealot elves, giants, sorcerers, and dragons. He thought he would be the hero, a leader of men, and the champion that saves the princess. Instead the closest thing to a princess turned out to be among their enemies, and he was no leader. It turns out poor Johnny Under (they had to shorten his name) was among the lowest of the low, a new recruit, and just another ranker.