Vellum: The Book of All Hours: 1 by Hal Duncan
It's 2017 and the End Days are coming, beings that were once human gathering to fight in one last great war for control of the Vellum - the vast realm of eternity on which our world is just a scratch. But to a draft-dodging Irish angel and a trailer-trash tomboy called Phreedom, it's about to become brutally clear that there's no great divine or diabolic plan at play here, just a vicious battle between the hawks of Heaven and Hell, with humanity stuck in the middle, and where the easy rhetoric of Good and Evil, Order versus Chaos just doesn't apply. Here there are no heroes, no darlings of destiny struggling to save the day, and there are no villains, no dark lords of evil out to destroy the world. Or at least if there are, it's not quite clear which is which. Here, the most ancient gods and the most modern humans are equally fate's fools, victims of their own hubris, struggling to save their own skins, their own souls, but sometimes... just sometimes... sacrificing everything in the name of humanity.