I have to admit I’m having trouble trying to piece this together - a boy who THINKS he is a girl, goes into a bathroom where there is a girl who thinks she is a boy and what happens? Beats the heck out of me...
It sounds like only one of the kids is transgender. The article doesn’t say, but I’m guessing biological boy who “identifies” as a girl has sex with another girl in the bathroom.
Just goes to show you, a teenage boy is easily aroused, for any reason whatsoever. Even severely confused ones who think they’re girls. The opportunity arose.