I read an essay that dealt with a much similar topic.
It debated whether you truly owned a book if you didn't mark in it,and made notes in the adjacent blank spaces. It explained that to properly own a book one must first have clearly in their minds what does it mean exactly to own a book.According to the author there are three kinds of book owners.
The first one owns all the best sellers,and classics plus the books that "you just need to have",but he doesn't read any of them.The author says that this person only own"woodpulp,and ink".
The second type of owner has a lot of books,some of them read,but most of them only dipped into.This person might want to be able to make those books "his own" but is kept back by the false respect of their physical appearance.
The third type has few or many(it could vary),but has read everyone of them,and are totally marked,and scribbled.According to Mortimer J Adler(the author) this person owns the book.
Although this essay is aimed at marking book to gain the idea or essence of it I don't think your case is much more different.
CK,you are an artists,and I'm lead to believe this by the idea that you just had. I think it would be cool to draw in your novels(or any books) cause it would be a way to mark it as yours. Plus,I've seen that things that artists had usually tends to have a uniqueness to them because its owner did something to it or marked it as his/her. This gives them a greater value.
Or so I think.
Oh,here's the link of the essay
http://radicalacademy.com/adlermarkabook.htm