There's something so poetic about one identity killing into another, fir better or for worse.
my interpretation is that this is all happening in the mind of someone else, the murder of the girl represents someone coming to terms with the fact they're trans.
But maybe I'm wrong, maybe the person is a trans woman, and this is a day dream where they think about coming out and being accepted by their loved ones, only for their fear and doubt to kill the girl and force them back into the closet.
(I'm not trans myself, please let me know if i've said something out of line here)
God this is such a cool experience, the descriptions are gonna stick with me along time!