Teens have explored different identities always. It’s a natural part of development.
I went - crazy hair sprayed hair a la Bonnie Tyler, to rock chick - skin tight jeans and stilettos, to goth with black finger nail polish to hippie all the way through to now - very boring middle aged SEASALT woman.
Exploring different identities and cultures has always wobbled parents - youngsters were not allowed to see Elvis or The Beatles for example because of the fears of the influence on them.
My guess is this is just play for them both. Might be the friend has hit the beginning of puberty and is trying an identity out. But I think the level of panic is OTT. I know the internet, porn and grooming is a risk but these girls don’t have access to any of that yet presumably.
I see teenage girls walking to and from comp in the shortest skirts and knee high socks - a very sexualised look if you hold that lens up. My stilettos would have been too - but I was oblivious. Victorian era according to AI: “teenage girls and young women engaged in subtle flirtation by wearing highly ornamented stockings or tightly lacing their leather boots to show off a dainty foot and ankle when they naturally lifted their dresses to step into carriages or walk”
I hope that we can raise girls into women that understand the patriarchy and how it’s shaped us, how we can choose what we wear and don’t need it to conform to satisfy the male gaze. That just because we dress a certain way doesn’t give anyone the right to disrespect us, harass us or assault us. That we have body autonomy. That porn often presents a warped depiction of sex that is mostly to satisfy male fantasy and is often degrading of women. That there are people out there who will have nefarious intentions but that we have rights and how to protect ourselves.
But for now, let her play. Let her have her innocence without letting a dark underbelly of society (of which there are only a few - most people regardless of sexual
orientation and identity are ‘benign’ all the way through to ‘good’ people) infect it through your fears OP.