Bibliomania is an extreme passion for books. If you spend all of your paychecks buying first edition novels, you can say you suffer from bibliomania.
The word bibliomania, inspired by the French bibliomanie, combines the Greek roots biblio, "book," and mania, "madness" or "frenzy." If you love books as physical objects, and you collect them furiously or compulsively, that's bibliomania. Merely loving to read might instead be called bibliophilia, with philia meaning "fondness" or "love." If your bibliomania interferes with your life, it might even be categorized as a hording disorder.