I will be using the students real names.

Yandere-chan: Ayano Aishi

Senpai: Taro Yamada (Or... Taro Aishi.)

Ok, so here's the story:

Ayano and Taro got married, and had two kids: Daitaro and Ayaka. Here is their story.

3rd person POV

Ayano Aishi, had succeeded. She spent most of her high school life stalking her crush and adoring him from a distance... and killing anyone who tried to take him away from her.

One Friday afternoon, she confessed to a male student name Taro Yamada, admitting her love to him. He accepted her confession, not knowing that seemingly shy, cute girl in front of him was an emotionless psychopath. Ayano was ecstatic, and immediately told taro everything that she had done for him. Killing from students to teachers. The only one she spared was her Taro's little sister.

Grief-stricken and horrified, Taro rushed away, but Ayano grabbed his arm, smiling sweetly as she reminded Taro that he had accepted her confession, and therefor they were destined to be together forever.

Taro resisted, yelling at Ayano and still trying to run away. Ayano refused to let him go. Her smile disappeared, and she warned Taro: "If you tell anyone, or you try to leave me, I wont spare your family this time." With an empty, emotionless smile, she released Taro, watching him stand there in shock.

Taro wasn't an idiot. He knew Ayano wasn't lying. So he agreed to stay with Ayano, for the sake of his family. For his parents and his little sister, he stayed.

Life continued. Taro and Ayano married the second Ayano graduated high school, and a year later they had their first child; a boy named Daitaro Aishi. Daitaro had black hair and bright, light gray eyes. Daitaro was energetic as a child, also creative and adventurous.

Taro was greatly relived that the child hadn't inherited it's mother's personality traits. Ayano was indifferent to the fact, and loved her child greatly, because she though of him as physical proof of the love between the two parents.

A year and a half later, Ayano had a second child. A young girl named Ayaka, who had black hair that she preferred to wear in a side ponytail, but she didn't seem to care about her looks. She had dark eyes and her mother's empty gaze. She was quiet as a child, rarely making noise unless necessary. She was wary and a rather clever child.

Taro was concerned about their daughter, worrying that she would grow up like her mother. He didn't voice his concerns, but did mention the fact that Ayaka was an extremely quiet child, and that he was worried that their daughter might be ill. Ayano assured him that this was normal, and said that she was the same way as a baby. Taro was not comforted.

Daitaro was constantly trying to get a reaction from his sister. He would try to do anything to provoke her, hoping that his sister would scream or cry. Ayaka did none of these things. Daitaro eventually gave up trying to annoy her, and they seemed to have a decent relationship, although it may become awkward at times, due to his sister's anti-social behavior.

Ayaka was indifferent towards her brother from the start, and his constant attempts to annoy didn't even faze her. She did get aggravated at times with childish attitude, but she shrugged it off.

As the children grew older, their relationship grew complicated. Daitaro started to constantly worry about his sister, after seeing her become a loner in middle school. He never understood her, and he believed that she could make friends if she just tried. He sometimes grew annoyed with her, demanding to know what was wrong with her. She would simply gaze at him coldly, and walk away whenever he got mad at her.

Ayaka didn't understand her brother, but as she grew older she noticed that her brother seemed to worry about her. In an effort to assure her brother that she was fine, she started to put on an act, smiling and acting like everyone else. Although this seemed to ease her brothers mind some when it came to her social life, he was still desperate for answers.

When Daitaro was fifteen he confronted his parents for the first time, demanding to know what was up with Ayaka. Ayano explained to him that there was nothing wrong with his sister at all, and that she was just a bit different from everyone else. Daitaro believed them, but vowed watched out for his sister as she grew older.

Ayaka noticed the change in her bother's behavior, as he seemed to spend more time with her. She didn't feel happy or annoyed or any other emotions that would be normal a thirteen year old girl, she only felt a faint bit of curiosity at her brother's behavior.

Their relationship got better, and Daitaro became less concerned at his sister's odd behavior, as he began to get used to it. He accepted the fact that this was just the way his sister was. He grew quite fond of her, and continued to try and understand his sister's strange behavior.

Ayaka was still indifferent towards her brother, but she tried to understand him more, also. They became almost like friends, and Ayaka knew she could depend on her older brother for almost anything.

When Ayaka became fourteen, she had accepted the fact that she was different. Seeing her brother smiling and laughing so easily, only reinforced that idea. Ayaka tried to figure out was missing. She started to become more observant of the world around her. She noticed that smiles were common. Laughter was also common. She even noticed one of her peers crying about her breakup with her boyfriend. She realized that these were the things that people called "emotions".

Ayaka chewed it over, and decided to talk to her brother. Her brother was frightened by the theory that Ayaka had no emotions, but tried not to let it show. They agreed that this was most likely the case. Ayaka was indifferent to the fact, and it didn't bother her.

Daitaro was worried enough to ask his parents, and they remained silent and avoided his questions. Daitaro had his answer. He vowed to watch out for his sister as she grew older.

The first year of high school was easy. Ayaka had perfected the act of pretending to be normal when she was around people. Daitaro spent as much time with her as possible, even though he was one school year above her. His friends used to make fun of him for spending time with his little sister, but it didn't bother Daitaro.

The second year, however, was an entirely different story...

Please leave a review on your way out. Opinions are much appreciated. :)

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Daitaro Aishi

Name: Daitaro means "Great First son" in Japanese, and Ayano like this named because it has 'Taro' in it. So therefor, he is named after his father.

Gender: Male

Age: He was born on May 1st. He is one year and six months older than his sister. His age will change throughout the story.

Appearance: Black hair that he keeps short. Light gray eyes that look thoughtful and kind at the same time. Tall for his age.

...

Ayaka Aishi

Name: Ayaka means "colorful flower" in Japenese, referring to her Mother's name, Ayano, which means "My color". Ayaka is named after her mother due to the similarities between their names.

Gender: Female

Age: She was born on November 1st. she is one year and six months younger than her older brother. Her age will change throughout the story.

Apperance: Black hair that she wears in a side ponytail, and dark, almost black eyes. She has her mother's empty expression most of the time