Identification is the process by which the reader or viewer associates with a character or work of fiction in film and literary studies. … The three most prominent concepts of identification as described by Freud are: primary identification, narcissistic (secondary) identification and partial

 

Fictional characters can influence readers in real life, a study has found. … 19 per cent of those said that the voices of fictional characters stayed with them after they had finished reading, influences the tone of their thoughts and even directly “speaking” to them.

The personalities are called fictional introjects, fictional alters, fictive alters, or fictives. Fictive Alters in Dissociative Identity Disorder