Fanny Crowne is a static character—that is, someone who does not undergo any major shifts throughout the story and remains largely the same. A sensible, good-natured, “nice” girl who blindly repeats everything she has been taught, Fanny is a product of the World State’s conditioning and representative of its average citizen. In Chapter 4, she scolds Lenina for seeing Henry exclusively for four months, arguing that it is “horribly bad form to go on and on like this with one man.” It’s clear she is a model citizen; not only does she adhere to the World State's custom of non-monogamy and promiscuity, she fully accepts the means by which the government regulates sex and reproduction, as demonstrated by her willingness to take contraceptives and get Pregnancy Substitute injections without question, even though she’s only nineteen.

Fanny is initially put off by Bernard Marx due to his "unsavory reputation" as the black sheep of the community. However, once he has grown in popularity due to his connection to John, Fanny changes her tune and expresses excitement when Bernard asks her to meet "the Savage" with him, further highlighting the ways in which her opinions are easily swayed by others. Huxley emphasizes Fanny’s lack of development in Chapter 13, in which, during the reader’s final scene with her, she casually implores Lenina to force John to have sex with her even though he does not want to (specifically because he does not want to). She removes emotion and consent from the concept of sex and paints it as a purely physical human need, an impersonal and immoral view that aligns with the values of the World State.