For Discourse, it might make more sense to do this:
A single “Book club readings” category
One topic per chapter (or less), with modposts as barrier markers, linked from the first post for easy jumping
One more topic for the announcement & wrap-up, each
All of these linked from a pinned index topic
Any extra topics aggressively merged into the canonical one
Of course, adapt to your needs, but I think that could work well.