A clothing store with an opera theme. Shirts, hat, jackets, and other manner of clothing can be found here, along with appropriately costumed representations of Disney characters.
A word of caution about buying clothing at Tokyo Disney Resort: Japanese clothing is small. If you're an American and you wear a large-sized t-shirt, buy an "L"-sized t-shirt here and I guarantee you it will be way too small. Making matters worse, they don't have sizes for larger (or even medium) sized folks at all. Unless you wear a small or medium-sized t-shirt, you probably won't be able to find anything to wear here, other than a hat. You can find larger-sized clothing at Japanese department stores, but sadly not at Tokyo Disney Resort.