I didnt read the story yet but from what im guessing, the ML was forced into the role of a woman to the point that being one was his whole identity?
Where can you draw the line between men and women? Just because you appear more feminine as a man does that make you a woman? No.
So when people see a person who dresses differently then the stereotype, people automatically assume you're a certain type of gender SPECIFICALLY because they choose to dress a certain way. As example, a butch isn't a man just because they dress masculine, they still identify as a woman
(On that note happy pride month!)
the whole plot is that crystal is a man, does that mean the story is simply about a feminine guy having a romantic relationship with another woman or more of a self-finding romance. ('_'?)
(You can Ignore this comment actually lmao, I was just bored and started typing, I'll read it eventually and find out myself haha)

This is just my personal preference, but if your going to make an entire story with the premise being that crystal is a man, how come crystal never becomes more masculine in any aspect other than his physical features, what changes? Nothing does. He doesnt dress differently his hair doesnt get cut even though there was a scene that showed him alluding to doing that once he went to the east. Like if you changed the title to "Crystal was always a woman" nothing would have changed.
I know i sound bratty and annoying, but if your not going to make your characters become more in tune with their true genders, whats the point in making them seem like they want to stay looking and acting like the opposite gender. Because personally if I was either of them, I would hate being FORCED to be the opposite gender, I wouldn't ever grow to enjoy or "accept that part of me" because that part never existed, I think writing them to be so okay with how their genders were treated was extremely unrealistic.
I know my rambling isn't organized but a few more things
One, maybe I just missed this but I feel like the author just never resolved their trauma in a proper way, I feel like they kind of just let it pass by.
Secondly, the pace of the story honestly focused too long on Crystal not being woman, I personally would have preferred if it got revealed to everyone by chapter 30 or 40, because then we could have had more moments where crystal could get mor comfortable with being a man, and I know that they are pretty much Trans but that wasn't what I hoped for when reading this, I wanted to see a narrative of two people who were forced into being something they weren't finally be able to be their true selves and be accepted for it.
I am done rambling I know all of you actually like how they were Trans and averted that expectation but personally I wished for something else.