Well, since I use digital books more than physical, that’s sort of a difficult question. I would say no more than like… 200 pages, with most probably averaging half that. But that’s a guess. It’s a bit nebulous I think.
Haha. I wouldn’t doubt if like, the guild staff use keigo. Honestly, I think I’d be more concerned about Megumin’s chuuni tendencies resulting in some weird, archaic language than I would keigo.
The graded readers will be easier, since it’s targeted at learners. Takagi-san will be harder, but will be more natural language (the book club folks will make this less difficult, though). If you have the time, I’d suggest reading both. If you don’t have the time, it’s probably best to ease yourself in with the graded readers to get used to reading first, and then starting Takagi-san after.
I think that is a quirk of Bookwalker that it differentiates between the two… Fiction isn’t a format, more of an overarching genre (which could range from mystery to sci-fi to slice-of-life). The only thing that fiction means is the author made it up.
Light novels are a format, and not necessarily a genre. I also don’t know if you can have a nonfiction light novel, to be honest. I’ve never seen one, but I suppose it’s theoretically possible. Either way, they are similar to novellas in English, which are pretty much always fiction, and under a certain page count. Trying to sort fiction and light novels separately is an odd decision, since most light novels, if not all, are going to be fiction by definition. 夜カフェ is fiction, after all. There are no signs that this is a biographical situation of any kind.
Where Bookwalker does class them both as separate genres, that means there are gonna be weird situations like this, where there is definite overlap between the two, but they forced themselves into one or the other.
Either way, my reasoning for 夜カフェ being a light novel: it’s short, has illustration inserts, and targeted for a younger audience (as light novels tend to be). It checks all the boxes. I wouldn’t class it as a full novel. While yeah, it’s also fiction, describing something as “fiction” doesn’t narrow the format much at all. Dune and Game of Thrones are fiction, but in their original formats, are definitely novels, for example. (Though there are Japanese light novel versions of both that reduce the stories to serialized, light reads which include illustration inserts, instead of massive novels.) My point being that you wouldn’t put 夜カフェ side-by-side with them in most cases…except that they are all fiction. That’s the only thing they would have in common.
Exciting, isn’t it!? Also, wow, after getting a good look at the first chapter art style, the shift through the series is fairly gradual, so I barely noticed at the time, but it actually has changed quite a bit.