love yourself ladies

a girl has been spending the night with my unreliable roommate for a week, the other day, when I looked up as they walked out of their room together, she hid behind his back so I could't make out her face. as she hurried for the door, I glanced at her from behind, a slim teenage girl with short soft black hair, white fleece sweatshirt and jeans with a bag hang across her shoulder. She is so skinny as if a summer breeze can blow her over, yet so ahead of her age, in a sense of ____, donno what's the proper word to put in, I can assure you it's not called maturity or even confidence, I don't wanna say she's thick-skinned either, it's just that, she is so unabashed of this whole sleepover thing as she keeps coming back regardless our dropped jaws. We doubt if she's even old enough to be in this situation, so my mom had a serious talk with my roommate, who is still a teenager himself. well, as usual, this sleek liar came up with some lame excuse: "my girlfriend got off work at 3am, so she came over to do her homework" right!
I'm not a prude, I've been through this phase myself, so my heart kinda goes out to that young girl, I wanna tell her that "love yourself and cherish your own body, cuz if you don't even care about it, who will?" anyway, who am I to judge here?