I was surprised nobody told me about (spoiler) the quite sincere same-sex interracial marriage early in the book, in which the one groom gives half of his worldly wealth to the other, and then they sleep together. Even if it isn't about sex, I'd think that scene would be better known if more than a few nerds like me read the book. It's in one of the greatest American novels, we've just gone through a great debate around marriage freedom, but actually reading it was the first time I came across it.