alright so i bought [this](https://imgur.com/a/Uj6seUY) book second hand several months ago, and while rearranging my books just now i noticed these stains. i don’t really remember it having them when i got it (although i could be misremembering). could this be mold? i don’t want to store it with the rest of my books if there’s a risk of it spreading… i genuinely can’t tell if it’s mold or just dirt or something (it’s pretty old).
any help would be very appreciated!
by terriblegaymer