Hello, I have this problem with my magazines and manga volumes- they became very stiff and hard. I've bought a lot of stuff in Turkey but here in Russia they...transwormed! You can flip and bent normal paperbooks however you want- but not these ones. My Post-It notes twist a little bit too.

My guess is that low humidity in my room has something to do with that, also keep in mind it's winter outside and high humidity (around 70-75 %).

I've bought humidity sensor and it says 20 % rn, temperature is around 23-24 ℃ .

So my question is... can it be fixed or my library just getting destroyed slowly? I am choosing an humidifier right now but some are very expensive or leave some sort of residue after using.