Lacking in plot and consisting largely of a relatively unromantic romance. That said, I actually liked the romance, at least intellectually, because Percy and Arsenic fall in love merely by reading together and sometimes having deep conversations about their various overlapping interests. There's no passion there that I ever felt, but there's a deep connection of the truly similar and there's no doubt they'll live happy lives together. It's generally not the stuff of romance novels, but there's a lot to be said for feeling truly comfortable with someone, and for an introvert there's little sentiment more powerful than not minding the company of another.

Aside from that, as I said, Reticence dearly lacked in plot, which is a bit weird for a steampunk adventure. If the romance had had plot or really any sort of character arc for either, that might have worked, but nothing happens but quippiness for the first half of the book. At about the 50% mark the actual plot, involving a trip to Japan to search for a missing spy and find a new kind of supernatural, begins. However, even then, it's not much of a plot, and it all comes together quite conveniently, and, frankly, didn't make a ton of sense to me.

Still, I did enjoy the book throughout despite those problems, because I do rather enjoy quippiness and the silly humor Carriger writes so well. A weird book this one, though.