This is a Sonic Heroes themed mini note pad. The front has Team Sonic with the Japanese logo. The back has all 3 teams with colored stripes. You can tell by the edge, that this is pretty thick/lots of pages. The pages have a light 'watermarking' of checkers, Team Sonic & the logo...so every page is an ad. The pages are also different color themes.

You can see these upper pages are blue, followed by orange ones (and then probably red too) This was a booth give-away or promo type item at the Tokyo Game Show in Sega's booth. Booth prize items like this, while free, tend to be uncommon since you had to attend to get one.