This Is How You Lose the Time War by Amal El-Mohtar and Max Gladstone
I read it, every passage made sense but when I reached the end I sat back and find myself unable to sum up the whole in a way that does it justice. It's a time travel story where the mechanics are fascinating but incidental, hinted but never expounded. It's a love story about enemies becoming friends, inseparable while also impossibly distant. Their address is clinical and tender all at once.
Reading this book was like the first time I tried persimmons, at a party last autumn. They taste like if a carrot were a fruit, like I ought to have known the flavor but had definitely never tasted it before. This book snaps and fizzles in my mind, every syllable feels important but ultimately is meaningful for its place in the larger whole rather than its component parts.