One common theme is extreme possessiveness. Yandere characters in these stories often view their love interests as their sole possessions. For example, they can't stand the idea of their loved one interacting with others, which often leads to stalking and isolating the person they love.
A common theme in yandere horror stories is the blurring of love and hatred. The yandere starts with what they think is love, but when things don't go their way, it quickly turns into hatred. For example, if the person they love shows interest in someone else, the yandere's 'love' morphs into a desire to harm or destroy. Also, themes of psychological manipulation are often present, as the yandere tries to control the life of the person they're obsessed with.
There's also 'School Days'. Kotonoha Katsura is involved in a complex and horrifying situation due to the yandere behavior of Sekai Saionji. Sekai's unhinged love for the male character leads to a series of tragic and violent events that shock the viewers.
There's a yandere horror story where a young woman moves into a new apartment. Her neighbor, a seemingly nice guy, turns out to be a yandere. He begins to manipulate her life, cutting off her contact with friends and family. When she tries to resist, he shows his true, violent nature. These stories often play on the fear of being the target of someone's unbalanced love and possessiveness.
People can also document any strange or threatening behavior. If it's notes or messages, keep them. This can be useful if the situation escalates and they need to involve the police. Also, avoid being alone with the person who shows yandere - like tendencies.
Well, in one of the stories, the yandere figure was a neighbor. This neighbor developed an unhealthy fixation on another neighbor. They would constantly peek through the windows to watch their every activity at home. They also left strange gifts at the doorstep, which were often items that the watched neighbor had mentioned casually in conversations. It was really creepy how the yandere neighbor knew so much about the other person's life just from observing and eavesdropping.
In another real - life yandere - like case, there was a student who was obsessed with a classmate. The obsessed student would steal personal items of the classmate, like their notebooks and pens, just to have something that belonged to them. They also sent anonymous and disturbing letters, filled with declarations of 'love' that were more like threats, which made the classmate extremely scared and on edge all the time.
In another instance, a man was yandere for his neighbor. He would secretly take pictures of her through her window. He then started leaving dead animals on her doorstep as a 'gift'. The woman was terrified and moved away after calling the police.
In yandere x reader fanfics, yanderes usually display intense emotions. Their love for the reader is not the normal kind; it's more of an obsessive love. They may have a dual personality where they can be extremely sweet and loving one moment, but if they feel threatened in their relationship with the reader, they can turn very dangerous and menacing.