This is the problem I’ve encountered. Anime is fine, it’s like any other show/entertainment but it really can attract the wrong type of people. It’s why I don’t put it in my profile. The person I’m seeing has plenty of “horror” stories like yours too and said they avoid people with that in their profile now even though they like it cause of how weird or obsessive people can get about it.

Kinda sucks cause IMO one of the best parts about it is the ability to create other worlds/universes that live action struggles to do. (Think ATLA anime vs Live action)