Now here's something fun!
It's a "megadrive pouch". This soft-sides pouch could be a pencil case, a pocketbook carry-in, or just a good way to store loose stuff. It's modeled after & shaped like a Megadrive game box for a Sonic game. (Remember, these looked different in Japan with primary colors & shapes rather than scenes) The back even has 'screen shots' & little vertical phrases about the game. The black rectangle on the front says "The worlds' fastest hedgehog". The zipper appears to go all the way around the edge so it would open like a book & even has 'spine' area title/decoration.
What's that inside? Looks like maybe a wallet with the same effect, or perhaps some interior mini-purse accessory? The pens there give you an idea of how big it is. (Looks like it's the same as the game box, most likely) This is a pouch with a very fun and creative collectible idea.