He who fights with monsters. Book one
(Book)

"Jason wakes up in a mysterious world of magic and monsters. It's not easy making the career jump from office-supplies-store middle manager to heroic interdimensional adventurer. At least, Jason tries to be heroic, but it's hard to be good when all your powers are evil. He'll face off against cannibals, cultists, wizards, monsters...and that's just on the first day. He's going to need courage, he's going to need wit, and he's going to need some magic powers of his own. But first, he's going to need pants."--back cover.