Harper Lee's novel To Kill A Mockingbird is told in the first-person past tense. Its narrator, an older Jean Louise Finch, confesses about a controversial time in her childhood (when she was still nicknamed Scout). Lee casts her readers in the role of her narrator's confidant, as though Jean Louise were our close friend who trusted us with a very personal story.
Even more interactive is the role readers play in Dracula by Bram Stoker. An epistolary novel, readers take up the parts of characters in the story, such as when Jonathan Harker notes his experiences in Transylvania at the beginning of the book: if we are reading Harker's diary, then are we meant to be in the role of a future version of Harker himself? Or, perhaps later in the book, when Mina and Lucy correspond, is the reader temporarily cast as character to whom the letter is addressed?
Another type of role casting is demonstrated by texts such as Jane Eyre. Charlotte Bronte's novel is self-aware, and the protagonist directly addresses the reader as Reader. This is neither like the conversational of To Kill A Mockingbird or the interactive roleplaying utilized by Dracula. The protagonist/narrator is conscious of the story's written form and recognizes the "presence" of an unspecified reader.
These variations of author-reader intimacy make different experiences for readers, whom, for writers, may not be real until this experience occurs.