Interestingly, during the Homestuck Official Discord’s readthrough, the HSO mods split the content warnings into two halfs and included “detransition” on Candy but NOT on Meat — presumably in reference to Candy!Roxy being a conscious repper.
I’m still pretty sure this is a mistake of the read-through’s framing (probably coming from people not creatively involved with Homestuck or at least not involved with the Epilogues) rather than an actual confirmation that that’s what it’s supposed to mean — because, yknow, only one character actually detransitions in The Homestuck Epilogues, and it’s Calliope. It seems pretty blatantly framed that way to me even:
Callie isn't personally offended by being called a girl -- they just don't consider it literally correct. The way they describe "being a girl" makes it seem like it was an identity they chose & performed rather than what they were just assigned. they go onto say as much literally:
but parts of this also strike me as a fib: i haven't got the passage handy, but i recall Calliope describing Caliborn being uninterested in humans & Earth until Callie's interest in them took root, with him then constructing his relationship to Earth in opposition to Calliope's -- but maybe i'm mistaken.
regardless, Caliborn berates & mocks Calliope for dressing up and presenting how she chooses, decrying it as playing pretend, but still chooses (as confirmed by the Epilogues) to perform maleness, as if maleness is the expected default and femaleness a superfluous and silly extension of that -- y'know, much how the patriarchy treats gender, and indeed, how the cispatriarchy often treats trans people's genders: it's normal and rational to want to be a man (or assert oneself as one), but it is backwards and regressive to want to be a woman (or assert oneself as one).
This (trans)misogynist understanding of gender seems to have been inherited and internalised by Meat!Calliope: they describe themselves as taking solace in having chosen being transfeminine, but REALLY, cherubs aren't biologically ANYTHING, and even though they don't mind being a girl. Calliope isn't saying, "I feel happier and less burdened by neutrality" (unlike Roxy) -- they're stating a sex realist & gender essentialist position. They literally cite biology:
They're being transphobic.
I think the reason that this has been incorporated into fanspaces as "Calliope is happily non-binary after feeling constrained by womanhood" is because, well, that's how Roxy presents his (at this point their) OWN gender:
it's a they household, a package deal; Calliope is implicated (without expressing it themselves) in Roxy's feelings about Earth gender:
they go on to describe the Earth gender binary as a weight & discomfort for them, especially the expectation of bearing children and the effects this had on them:
which are all really sensical reasons for somebody assigned female at birth to reject that assigned gender, but totally nonsensical reasons for Callie as a cherub to detransition. Indeed, when Calliope (briefly) talks about their own motivation on their own without being filtered through Roxy, it's presented as them feeling guilty about transitioning & that choosing womanhood is a reification of gender norms and that is in part responsible for the proliferation of misogyny (under exclusively a sex-based oppression model, no less):
Callie and Roxy are presenting transitioning to womanhood as a regressive reification of misogyny, and that detransition is the progressive solution to those regressive gender norms: they treat a trans woman detransitioning as the same action as somebody assigned female at birth transitioning.
As nuts as it may sound, I'm pretty convinced this a facet of the intended reading, because check out the canonically transgender Jade Harley's response to the idea that womanhood is a regressive choice:
is she concerned that the Rogue of Void's insistence that other people share the nothing-gender he plucked from the void will eventually turn upon herself, a woman with a penis? Is she worried about what "dichotomous human biology" might have to say of her?