oooh, I see. That isn't usually how I've seen the word used so I think that is where I got confused. (I'm used to folks just calling femme guys exactly that: femme guys. I see folks use demi-girl for folks who feel mostly like a girl, so refer to themselves as a girl.)
I'd more often see genderfluid applied to a character like this but that is not my decision and I'm happy to have the work as part of the jam.