So in most fictional characters with No Fourth Wall, the characters will never address you with any gender-specific terms, and you just pretend that the character correctly guessed your gender.
But sometimes, the character does assume your gender.
http://tvtropes.org/pmwiki/pmwiki.php/Sandbox/CharacterAssumesYourGender
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So in most fictional characters with No Fourth Wall, the characters will never address you with any gender-specific terms, and you just pretend that the character correctly guessed your gender.
But sometimes, the character does assume your gender.