Satan's Perfect Match

In an alternate world, named Olinn, where the police don't exist except in large cities and everything is run by crime families, 2 killers- the fox and the raven- have been slithering in the dark where even the shadows can't reach. The killers meet and the string leading them together all this time finally snaps, and they know that they were meant to be. The Fox was born a psychopath and he kills for the thrill of it, while the Raven has been forced into this grim fate with a previous promise that further altered his life forever. A few weeks after the Fox and Raven meet, they meet again and the Raven steals the Fox away to his own home. The Fox and the Raven end up teaming up to find and kill the Fox's twin brother- but when two psychopaths stay in each other's company for too long, will they kill each other or fall in love in the process?