Ok, this is one I've been thinking about picking up for a while, but a question for regular readers: is the MC actually even yandere? I read the first few chapters a while ago and she got, like, kinda possessive while drunk, but then literally nothing like that happened again.
Alright, so, I have been thinking about this for a while, and I think I might have an answer (or, you know, I could be way off base, this is pure speculation), seeing as I've just read another manhua with a character referred to as yandere in the title ("Is it Normal to Raise a Yandere Heroine as a Villainess?!"), and the character in the title actually has almost the exact personality as Jolene here, at least in the early chapters - sweet on the outside, cold and calculating on the inside. So, my guess is that the Chinese nerd culture adopted the word "yandere" and, over time, adapted it into its current meaning (which happens in linguistics all the time); specifically, it seems to have lost its denotations of "love-obsessed and willing to murder" while retaining the contrast between the character's innocent public face and their more sinister and darker internal one.