I dunno, I think this is more of a case of an edgelord gone wild and the marks of a complete spoiled brat.
AFAIK this is just sick shit she thought. Not done, or at least it had better only have been thoughts.
She's an adult woman who's never learnt how to behave like a civilised adult, or have some modicum of control over herself. She needs to learn in the real world, this shit doesn't fly. It's not cool or gothy and there's nothing impressive about creeping people out with her sick shit. She needs to control her temper and her twisted little urges or she can forget ever getting a job or moving out away from her parents, or worse..... She wants a ticket into the world out there, she needs to behave.
She probably got into this stuff at a younger age, creeped people out and was like "oooh cool" and no one else ever told her off on it, until now. but it's high time she learned how stupid it was to be like that and it's about time to cut the edgy psycho nonsense and grow the fuck up.
But of course she won't, it's oh so important to her identity, can't threaten that! / sarcasm.
I really don't know what it takes for someone to stop this kind of satanic nonsense. I wish I did.