ACC

''author-created character'', Internet slang, referring to the practice of creating a new character wholesale who is added into a fanfic's cast of 'official' characters. (The characters created by the official original creator are not considered ACC.) The practice is generally discouraged unless the character plays a small role and never overtakes the existing characters' importance in a story; those that do are often accused of being "Mary Sues" or "Self Inserts".