Brandon Graham 
King City #1 [EPUB ebook] 

When life itself seems lunatic, who knows where madness lies? In King City, that’s where! Joe is a young man with no home, no purpose, and almost no friends… though he does have a very special cat. With a simple injection, Joe’s cat can be anything: a weapon, a tool, or even a cuddly companion. But what — if anything — can transform Joe? Whatever it is, it can probably be found in King City, an outrageous semi-futuristic city full of spy gangs, alien porn, and reasonably priced diners. A word of caution: Avoid the meatloaf.