Danger Pay: The Christopher Danger Series, Volume One.

In 2065, the world has finally tipped over the edge. Between wars, death, destruction, and the lack of an overriding policing force, things needed a change. In comes the bounty hunters, policing policies and laws of their own, they hunt down crimials, for money of course, and keep the lands safe...ish. Here lies the best of them all, Christopher Danger. He's met with the best, the worse, but there is one thing he's yet to explore, a different reality. A bounty has taken themselves to that new world, and with his spotless record, there isn't a snowball's chance in hell, he'll let that lonely soul get away.