Let me tell you the story of how children can accidentally step into adult spheres of kinks. It's a slow process.
As I mentioned earlier in the thread, I liked vampires as a kid. I was not encouraged to dress as one, instead I was encouraged to get into some classic lit and some music, old films, folklore.
Another friend of mine didn't have parents who did that. She, without her parents knowing, went online and joined chatrooms and communities. Her parents also thought their darling little girl didn't have access to this kind of thing, but it was pretty easy as in each generation kids always find ways to outwit parents with tech. Unless the parents are down on it like a tonne of bricks.
Anyway, she joined these communities filled with other vampire obsessives. Some her age and some far older. She lived for this stuff, and her parents just thought it was good she had an outlet. It was all she would talk about. She did have vampire fangs and little homemade amulets of fake blood. All bloody stupid tbh, and we all thought she was being daft, but whatever.
It went on for years. When she was 16 she went to meet a friend of a friend (an older boy) in town. Turns out he wasn't 18 like he'd said, but 24. He actually bit her. She had to go to A&E if I remember correctly and it turned out this chap had been going around the online community preying on young girls taking their virginity, acting like a "Sire" vampire. Three of her online "friends" were also targets. They were all 16 or over so I don't think it went to court, but tbh I can't remember much now. She ended up traumatised. The parents couldn't fathom how they'd missed it, despite their child having had behaved so weirdly for years.
Vampires and animals are both fun things to be into. They're also things that are heavily fetishised. Being willfully blind to your child being into something that comes with a whole world of crazy, and not enforcing regulations is just wrong. Liking vampires is cool. Wanting to be a vampire and acting like one is not. Liking animals is cool. Acting like one is not.
You're being willfully ignorant. The fact she even knows what a Therrian is? Come on.