Toast
I will begin by saying I hated the first few chapters, I had little to no idea what was going on, it's so jarring. The full answers won't come until the final few, but I was completely on board by that point.
The sheer inventiveness, the the twisted darkness, the hilarious tangents, hard to believe people can come up with this stuff, hard to believe we let them walk around freely!
Set in a post apocalyptic future, the story harks back to earlier times in the main character's life, a time still in our near future, where global warming, inequality, extinction, and biotechnology are really running amok.
The initial difficulty with the structure and setting is paid off handsomely by the end, masterful storytelling. Though be warned to get there you will go through detailed accounts of modern international child abuse. A book set in the future but about now. Pulls no punches.
The sci-fi tech is awesome, the genetic hybrids are realistic yet fantastic, as is the brilliant (and twisted) language usage - the in world game Blood and Roses and the fridge magnets really stood out.
Contains the greatest discussion about toast in all literature.
As well as many other almost throw away philosophical asides, some artist's decreeing the main produce of humanity to be corpses and rubble, or how our aboreal ancestors enjoyed shitting on their enemies, and how all our planes, bombs, and rockets are just variations on this.
Very smart on how an actual apocalypse may play out, we would not have to simply reinvent the wheel, or the stone age, modern society has no manual, can't be just put back together, the complexity is immense, once it's gone it's gone.
Modern hyper capitalism, good old greed, well meaning terrorism, and our ubiquitous creative stupidity are brilliantly skewered.
Enormous body count, twisted, brutal, very funny and absolutely brilliant. Sign me up for more of Margret Atwood!