The twelfth book: #12 The Lusiad
The Lusiad didn't work for me - ticking several boxes there. Set up as a poem, the story went lyrical and allegorical - rarely describing much and getting lost on tangents. And not in a good way. The focus is less on telling the story, and more on rhymes, and in this case that just bored me.
Then it got set up as a series of monologues. I've mentioned before why that doesn't work for me - see La Celestina - and the 'arguments' (as they're called) may expound on feelings a lot, but they are terrible at actually telling a story (something plays do by being visual instead). It works if it's about a discussion, but not as much when you're talking about something more adventurous like exploring and discovering new countries.
Probably the most interesting part for me were the footnotes including in my edition, explaining the historical facts and such behind the story. At least there was something I could get out of it.