I bought this, but gave up partway through. The introductory text has some creases, but the rest is unused. I also have all the answers to the correction problems. I will also include the Daily Rokko (law book) that I purchased with it. I purchased the "Deru Jun" (order of appearance) book here. It is used. It's quite a lot to buy this whole set. Please consider it. Please feel free to ask about price reductions or any questions you may have.