To unlock the "Extras" option at the main menu, win the World Queen Contest. Select the option to create a new character and choose to continue from your saved game. A new option will appear. Select the top choice to continue with your original character. Select the bottom choice to play with your new "Extras" character.
As soon as your shop rank goes up, save the game. Then, all of a sudden, you lose. Turn off the DS power, restart your game, and simply try the contest again!
