I love this book! It presents you with 6 short stories (each one around 12 pages long or so, but the last one is only about 2 pages). On one page it presents the Japanese text, and on page opposite of it you will find a translation of the phrases. Towards the back of the book, you will find another 50 pages or so of additional notes, which explain things such as words or grammatical patterns and other such things. There is also a japanese-english dictionary containing the words that you find in the stories. I love this format, because everything you need is right here in the book, so you don't have to constantly be looking up phrases on your computer or electronic dictionary. You can just lay back, relax, and read! However, the format of having the notes in the back of the book make it a little annoying, since you have to keep flipping back and forth, but you should be alright if you use two bookmarks to keep your place.
The stories themselves are real Japanese, just as the title says. These aren't watered-down stories designed to be easy for beginners. I've only read the first story so far, and I found it extremely challenging. The translations and notes and everything really helped out a lot. Although it took me over an hour to read the first page, as I continued on, I found that my speed was increasing quite well. I've completed advanced classes in Japanese in college, and I could hardly understand any of the sentences in the first story. However, the notes are all so helpful, I feel like I learned enough from just one page of this book to make the price worth it. If something is difficult to explain in English, the author will sometimes provide you with additional sentences for the purpose of helping you understand how a certain phrase or grammar point is used. There is furigana over the kanji the first time a word appears. I really like this, since it forces you to learn the reading of the words when you encounter them again later in the stories. The included cd is also very helpful, since it lets you hear how to say everything naturally.
This book assumes you have about an intermediate (or higher) level of knowledge with Japanese. For someone who has only completed intermediate classes, you may find the book fairly slow to work through, but as long as you actually study and try to learn from the material, I don't think you will have a problem.