^I don't think Jessica qualifies as Yandere. Going into 1.2 story spoilers, She set up the whole horror story at Green Lake because she thought Jennifer would like it, as Jennifer loves horror. Jennifer got Jessica into horror stories when they were younger, via reading Jessica the horror stories that Jennifer wrote as a child. After Jennifer moved away Jessica mostly grew up in the woods with creatures, was experimented on for awhile, and her social skills are underdeveloped because of these circumstances. She likes Jennifer and wants to stay with her, however Jessica hasn't killed anyone that comes between them. Jessica locked people in her cave that she wanted to be her friends with, because she didn't understand why that's bad. To her the whole Green Lake affair was a childish game, because Jessica still has the social skills of a child. So I don't think she's a messed up Yandere in the slightest, despite her love for the horror genre, various mistakes with social understanding, she's rather pure at heart. What she needs is care and love, people that can help her social skills grow, and show her the greater world as she grows up into a proper adult.