I can say from experience, it doesn't work well. Everytime I read I end up with a cat or 2 laying across the book. I can't read the print through them. Then I tell whomever "You are a cat. Not a bookmarker. See this? (hold up scrap of paper) This is a bookmarker. You (point with said paper) are a cat" And what happens? My "bookmarker" slaps the crap out of my scrap of paper. Or, in Chinas case, she steals the paper and slobbers on it. Of course what I truly love is when it's a library book (an expensive one to boot) and Jake decides that's the best thing to sharpen his claws on....while he's draped across the book. And Isis loves to chew on the corners of hardbacked book.
So, cats as bookmarkers, does not work.
So, cats as bookmarkers, does not work.