Huhu baby, we're finally getting some of that sweet Shinobu lore!
Once again, trivia time:
-The entire art style for this episode is reminescent of emakimono, an old kind of japanese narratives drawn on a long scroll. It really helps getting the viewers immersed in the 400-year-old story :)
Like you said, this episode is pretty much exposition and the anime adapted this part of the novel down to a T, so I don't think I can add much more for the time being.
I'm really looking forward to the next 2 episodes!