The one not called Jamie, is not wanting him to ask her gender. She obviously obsesses about being asked gender. . Gender is usually Male or female, two choices, a binary decision. . The suggestion is that The one not called Jamie does not like to be forced into one of two options. . Nothing lead to the response. It appears the one not called Jamie is obsessed about it and responds this way regardless. While John, may be correct, I think the piece only shows sensitivity to the issue, not necessarily a personal interest.

"Binary" has several meanings. They all have a sense of "double" or "two." Binary can mean "limited to exactly two possibilities: one or the other, nothing else and nothing in between." The "binary system" used by computers is a numbering system in which all values are expressed by just two digits: zero and one, nothing else, and nothing in between. To "put something in a box" or "box something in" can be an idiomatic expression meaning "to identify a person with a classification that is too rigid." For example, "everyone is either an introvert or an extrovert." It is a form of stereotyping. If you say to me "you are a typical introvert," I might object. "Don't label me! Don't classify me! Don't try to box me in! I am a unique human being and I do not fit any single category." I personally am finding it hard to keep up with the current terminology. In the last decade or so, our understanding of gender identity has become complex. In recent years, the term "non-binary" has come into fashion to express ideas about complex sexuality and gender identification. Jamie would probably describe--see, I am stuck because I don't know whether to write "himself" or "herself!" Let me try again. Jamie would probably self-describe as "non-binary." Jamie thinks that Grey is going to ask about gender, and try to classify Jamie as "male" or "female." Apparently Jamie gets asked that a lot, and hates it. She objects "don't try to classify me 'male' or 'female,' don't try to put me in a binary box, I am neither male nor female." Checking Wikipedia, I find that "non-binary" redirects to "genderqueer," and that Wikipedia says: "Genderqueer, also known as non-binary, is a catch-all category for gender identities that are not exclusively masculine or feminine‍—‌identities which are outside the 'gender binary' and cisnormativity.' Genderqueer people may express a combination of masculinity and femininity, or neither, in their gender expression."

Binary box here means gender-binary: the idea that a person is either clearly and fully male or clearly and fully female. Apparently, Jamie has a gender identity that does not fit neatly into a male or female box. Jamie suspects, for some reason not clear here, that Grey is trying to force him/her to admit either a clearly male or female identity -- force Jamie into one box or the other.