At the main menu, highlight the "Options" selection and press A + X to start a mini-game.
Start a game and do not rescue anyone. Eriko will lose more clothing with each lost friend. By the time you reach Level 6, Eriko should be in nothing but her underwear.
There are a total of three ending in the game. One if you save all friends, another for saving just one friend, and a third for saving no friends.
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