a yandere is a girl/boy who would do ANYTHING for someone they love. Some common yanderes are Yuno Gasai from Mirai Nikki and Ayano Aishi from Yandere Simulator.
Contrary to the popular belief that it is the opposite of tsundere, it describes an anime character who is either psychotic or violent or both, and shows affection to the main character. Became a popular moe genre after the airing of the last episode of School Days. One of the best character is Yuno Gasai from Mirai Nikki
A character, usually a girl, who fits the archetype of being genuinely kind, loving, or gentle, as well as obsessed with their love interest, sometimes demonstrating this through violent behaviour often killing those who try to harm,take or talk to their love interest.
Source : wiktpedia (yes it's spelled that was)
Betty:So Percifiony wants to take Steven away from me...
Betty:Welp that's fineI'm not a Yandere so I'll respect that he doesn't love me and move on.
Popularized in by the anime/visual novel School Days, yandere is a term for a psychotic girl who's only character traits are being cute or moe and random psychosis. The plot of a yandere story is that the main character falls in love with a girl who isn't the "yandere", where the yandere decides it would be a good idea to kill the love interest, any possible love interest, and finally the main character, because of love. Typically there is no reason for this psychosis because writers are usually lazy.
Rena from Higurashi is not a yandere.
Rena is not a yandere.
RENA IS NOT A YANDERE