Reaper: Aftermath - Reaper, #2

Gregory ended the world. Can he save it? It's been five years since the Reapers ripped Gregory's family apart and invaded Earth, leaving behind a wake of decimation. Gregory and a small group of survivors now scavenge the wastelands, living in constant fear of discovery. Weighed down by relentless blame for the planet's destruction, Gregory seeks to make up for his past mistakes. He gets that chance when a surprise attack forces him through a Reaper door.
Gregory finds himself in a bizarre place with no way back, a place that may provide answers to the Reapers' past and where they came from. Can Gregory find a way to destroy the Reapers and restore order to his broken world, or is the human race doomed to lose the war against these ruthless monsters?