Shinkai Makoto drew the illustration for this book. Note that I wrote "the illustration," not "illustrations." There's only one illustration, and you can see it below.
This book is more expensive than most novels, possibly because it's printed on larger and thicker paper. I really like the larger font. For a slow reader (of Japanese language) like me, it makes a big difference. In fact, I doubt I would have been able to finish the book in almost exactly one week if it were a small book. And that's while still doing my usual stuff, too, including creating the kanji list for Mokke 4.
As far as the story is concerned, it's somewhat unusual and perhaps even a bit unrealistic, but if you like shoujo manga (but this isn't a manga), I'm sure you'll like the story. It's about a 10-year old boy, Ooe Saku, and a 10-year old girl, Kawahara Sunao. Due to an unusual circumstances, the boy disappears and returns exactly 7 years later, without changing at all. In fact, as far as he's concerned, those 7 years did not happen. He came home and 7 years somehow went by for everyone else. Doctors give a bullshit reason for the situation, of course. Actually, one of the doctors is featured as a really nice guy, but as far as I'm concerned, that's 100% B.S. Maybe it's not so unrealistic in Japan, but I don't know about that. As an American, I know there are no doctors like that in this country. If anything he was probably being nice because Saku-kun is an interesting specimen. Okay, that's enough sidetracking.
Anyway, the situation is that Sunao-chan is now 17-years old while Saku is still a 10-year old. That's really it. I think it's a wonderful little love story or sorts. Obviously, there's a lot going on, but I'm not here to translate the book or anything like that, so I'll just leave it at that. Enjoy the scan.