A possible origin of the Yandere tropeYandere may have emerged as a deconstruction of the Yamato Nadeshiko archetype: a eternally serene woman who always puts the needs of her family and husband before her own. A yandere is all of this driven to the logical extreme and then examined realistically: a sentient individual put in such position would invariably experience enormous strain. Sooner or later she would snap at the slightest provocation. Ironically, it is this realistic take that makes a yandere so endearing to the audiences, often even more so than the traditional Yamato Nadeshiko. (Granted, there would realistically be a wide range of possible responses other than going Axe Crazy, but this one is definitely the most entertaining to watch!). Compare with the Violently Protective Girlfriend who can become Axe Crazy when the love interest is in danger but is otherwise MUCH more stable mentally. See also Living Emotional Crutch for a reason why she goes from affectionate to murderous.
Why Yandere can be perceived as attractive
- Someone who is crazy for you is someone who is crazy for you.
The Trouble with YanderesA main problem with a Yandere is that a poorly-written Yandere is easy Scrappy bait. As outlandish as the trope can be, Yanderes can still be likable as long as they have elements of sympathy with them, but alas, there are a few that lack that key redemptive trait. A Yandere written to be unlikable is more than likely to be a villain of some caliber, planning to cause harm to a more level-headed character in a fit of blind fury simply because their dream relationship fell apart. Another bad sign for a Yandere is if he or she suffers from Erotomania, and delusionally believes that the person they love is in love with them when in reality, the person is either indifferent or wants nothing to do with them. Unrequited Yandere attraction never ends well, and can be very ugly if the Yandere goes off the deep end. It is of the best interest for a good story, and all-around just to be taken seriously, to not have any main villain be motivated by Yandere leanings, and instead focus on it rather being a secondary character attribute or malady.
If you don't read the unabridged version I wrote especially for you, I'll gouge your eyes so you will never look at another trope!... Okay~?