I will give you a little push if needed:
Checking the lowest part of the Central Tower Area again might be a way forward...
Certainly! There are two other books, one of them is in the Dungeons area (Corris's first major area)
The second one is also in town but only after finding a girl at the top of the ruins area (there is also a CG scene to unlock)
After that, a major event can be seen after beating the final boss.
Good luck! And thank you for playing! I'm glad you enjoyed!
Thanks again, I got the True End with Corris and also finished it with Sirius.
Really a great game, the gameplay is fun and addicting, the pixel art is awesome (the only thing I would change is making the sex scenes at least a bit longer, since they are mostly a couple lines long now).
Also very noteworthy is that it was released as a finished game (while nowadays these kind of games here always end up in an unfinished limbo fueled by Patreon money) and also free (though I ended up paying the 12$ anyway because you deserve it).