After The Fall - Edward Ashton

Part alien invasion story, part buddy comedy, and part workplace satire, After The Fall by Edward Ashton, author of Mickey7 (inspiration for the film Mickey 17), asks an important question: would humans really make great pets?

Humans must be silent. Humans must be obedient. Humans must be good.

All his life, John has tried to live by those rules. Most days, it's not too difficult. A hundred and twenty years after The Fall, and a hundred years after the grays swept in to pick the last dregs of humanity out of the wreckage of a ruined world, John has found himself bonded to Martok Barden nee Black Hand, one of the "good" grays. Sure, Martok is broke, homeless, and borderline manic, but he's always treated John like an actual person, and sometimes like a friend. It's a better deal than most humans get.

But when Martok puts John's bond up as collateral against an abandoned house in the woods that he hopes to turn into a wilderness retreat for wealthy grays, John learns that there are limits to Martok's friendship. Soon he finds himself caught between an underworld boss who thinks Martok is something that he very much is not, a girl who was raised by feral humans and has nothing but contempt for pets like John, and Martok himself, whose delusions of grandeur seem to be finally catching up with him.

Also, not for nothing, something in the woods has been killing people.

John has sixty days before Martok's loan comes due to unravel the mystery of how humans wound up holding the wrong end of the domestication stick and find a way to turn Martok's half-baked plans into profit enough to buy back his life, all while avoiding getting butchered by feral humans or having his head crushed by an angry gray. Easy peasy, right?