Some of the book clubs in the informal list are things like “various works by xyz author” or “various works with this theme” stuff like that
雨でも晴れでも is one series
This discussion seems a bit like “what’s the difference between a light novel and a regular novel?” It’s probably more productive to ask that question on the informal book club thread, fwiw.
As the person running the offshoot, I don’t think of it as being informal, but like if @Megumin wants to put it on the list, I won’t object either.
