I can't say that I've read a book over 100 times, perhaps the closest to that count is A Christmas Carol which I've read over 20 times.

Centireading reveals a pleasure peculiar to text lurking underneath story and language and even understanding. Part of the attraction of centireading is that it provides the physical activity of reading without the mental acuity usually required.

— Centireading force: why reading a book 100 times is a great idea by The Guardian (Stephen Marche)