If the author has any sense of subtlety, the resulting character won't share their name or alias , but it's still easy to tell who that "new character" is. The self-insert is very often a Mary Sue ; as a matter of fact, the original Mary Sue she who gives that trope its name was born from a parody of the standard Self-Insert Fic. The main rule is to never put the character in a high-ranking story position, although they may be the narrator. The Self-Insert Fic has two primary varieties: the Self as New Character, where the author simply opens the top of the story and drops a copy of themselves right in , with a few smiles thrown their way to acknowledge their presence and a few lines chipped in, and the Self as Existing Character, where the author finds himself forced to take over the life and sometimes the body of an existing canon character, without necessarily being restrained to staying "in character" for their new role. Note that self-insertion isn't a bad thing.
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