Fun with defacing library property!
In the local library's copy of Kurt Vonnegut's Mother Night, someone has made copious sloppy, chicken-scratch pencil notes throughout, as though prepping for an essay to be written later. This is what the last two pages of the book look like (I've blacked out the actual end of the story, in case you want to read it, which you really should, because it's tremendously good).
If you look closely, you can see that someone else who borrowed the book after the note-taker had a note of their own to make:
"If you must deface books, at least have the decency to do it legibly." Awesome. It's almost worth all the scribbling just for that.
And then, in Vonnegut's Bluebeard, I found a few more pencil marks -- some underlines and check marks, though no actual notes as in Mother Night. The weird thing, though, is that there is literally one single sentence in the entire book which has been marked with a yellow highlighter, on pp. 201-202: