Books bring out the weirdness in people, not the subject matter. I’m referring to the actual, physical object that is a book, because everyone has their book quirks.
I have a friend who treats his books like priceless artifacts. Whenever I borrowed a book from him in high school, I was given strict admonitions against breaking the spine or dog-earing pages. That was hard for me because I was borrowing 500-plus page fantasy epics and I always loose my bookmarks.