The book is set across three different eras - the first I found the most interesting, with it being an alternate history late 1800s America where gay marriage is legal (and people even do arranged marriages for it). We then jump 100 years forward to a Hawaiian living in America. It gets a bit confusing here because the main character's names are reused (which made me think this was going to be like Cloud Atlas?) but they're not actually connected in some tangible way, although storywise they are sort of similar. Then we jump forward another 100 years for a dystopian, pandemic-ridden America where gay marriage is now banned in an attempt to increase the population. Honestly you could have just turned one of these eras into it's own book and I probably would have preferred it more!
A common theme across all 3 stories is the uselessness of at least one of the characters in each due to their passivity. Which I visit makes for some frustrating reading. And then I finished the book and it's like, well what was the point? But maybe that's what you get with Yanagihara books. A bunch of people suffering.