This appears to be some kind of cloth covered notebook or book. What's inside? Is it blank like a diary? The cover seems to be made of (or covered with) blue-jeans type material. The Secret Rings logo & border accents are on the cover, with what is likely the title in Japanese. You can see the stitches all around the edge of the cover.
Supposedly, this wasn't actually released, except as some kind of "prize" to the people who worked on the game. Do you know the story behind this covered book & what's inside?