|Strength||Dependent on Physical Education|
Yandere-chan has fair skin, black hair that is tied into a ponytail and grey-blackish eyes. She is 165 cm tall (5 feet, 5 inches), 43.5 kg (95.90 lbs), and has average-sized breasts. She's seen wearing a white and navy blue uniform shirt with a red mini scarf, a matching navy blue skirt, black stockings and black shoes. Her uniform can be customized. In all uniforms except for Female Uniform #5, she wears her signature black hip-high socks.
Yandere-chan is, as her name suggests, a yandere, one who will go to any lengths, even murder, for her love. Between a sociopath and a psychopath she is more of the former. She suffers from a fictional type of insanity.
In the first intro cutscene, Yandere-chan was not inherently a yandere; she was coaxed into it by Info-chan, and was apprehensive of the idea of killing another person. She is just a love-hungry schoolgirl who wants a boyfriend. She didn't even seem to consider killing Osana before Info-chan brings it up.
In the second intro, instead of this, Yandere-chan is very emotionless, apathetic, and speaks with a deadpan expression since as far back as she could remember before meeting Senpai for the first time. She'd do anything to prevent people from getting with Senpai, even if it means killing them, as Yandere-chan does not have the ability to feel emotions, empathy, or remorse. She does not feel guilt or shame for harming others. She knows what the general people consider to be "wrong", but she just doesn't care.
In both intros, Info-chan is immorally wrong to Yandere-chan. So even if Yandere-chan in the second intro is not right, she still must have morals of some sort. No matter what, Yandere-chan is a blank slate whose personality is determined by the player's actions, but all Yandere-chan's have the capacity to commit each of the possible actions in the game.
Yandere-chan's "hobby" is trying to convince everyone around her that she's a normal girl. She buys manga, plays video games, and rides a bike to project the image of a normal girl. However, she does not enjoy any of it. She isn't incredibly talkative at default and will only speak when necessary.
A few days before the game begins, Yandere-chan meets Taro Yamada and her sense of right and wrong became completely guided by the goal of obtaining him for herself. YandereDev has stated that Yandere-chan is a person who has never taken a life or harmed another person before meeting Senpai. For example, Yandere-chan tried to determine if she could experience any kind of enjoyment. She experimented by killing insects. When she discovered that killing insects brought her no joy, she decided never to experiment on animals, for that it would just come to the same conclusion. This backstory was later slightly altered to suggest the possibility of Yandere-chan killing an animal instead of some insects, but with this backstory ended with similar results. Thus, Yandere-chan does not kill for fun.
In the original intro cutscene, Info-chan says "So, history is repeating itself, huh? Time to test a theory..." after Yandere-chan rushes to school after running into Senpai, and "I'm sure you could. It's in your blood, after all," after Info-chan asks Yandere-chan to murder a fellow student, suggesting that Info-chan knows about the nature of Yandere-chan's family.
According to Basement Tape #1, Yandere-chan's mother and grandmother were yanderes as well and kept their obsessions tied to the same chair. In fact, the line of yanderes goes back very far. YandereDev imagines that Yandere-chan's great-great-great-great-great-great grandmother wore a bloody kimono and wielded a knife. When her parents were in high school together, her father was Yandere-chan's mom's senpai. Yandere-chan's mom was a yandere girl in school, and killed a girl in 1989. YandereDev explains this in his blogpost "Halloween and DLC".
Most women in Yandere-chan's family want to give birth at a young age, like 19. Yandere-chan's great-great-great grandmother was born in 1910. She will be 107 years old in 2017. It has also been a family tradition for several centuries that when an Aishi woman marries a man, the man always adopts the wife's surname. It is most likely that there are no male yanderes in the family. When a female Yandere is born, there are always slight differences between each generation, but each Yandere are not all clones. Their personas aren't more or less strong either.
Before meeting Senpai, Yandere-chan was just drifting through life without any purpose. Yandere-chan only met Senpai a few days before the beginning of the game and she changes as she no longer cares about right or wrong like she did before the encounter.
Yandere-chan acts like a pervert toward Senpai, wanting to go into the Boys' Shower Room to admire him. Even so, what she feels isn't lust, but more like seeing color in a grey world. In fact, it might not even be romantic, since Senpai just seems to give Yandere-chan new sensations.
If she ever accidentally hurt Senpai, she would feel a mixture of depressed emotions. However, Yandere-chan is okay with mentally traumatizing Senpai in order to eliminate a rival.
Yandere-chan couldn't object to anything that made Senpai happy, so long as it isn't another girl. Because of that, Senpai could use her if he wanted. However, if he insulted her she'd punish him and maybe even break him to fit her ideals.
Senpai isn't close with Yandere-chan and he doesn't know much about her. He usually never notices Yandere-chan as she can stalk him after school, depending on how the day went. However, if she stands near him for too long during the day then he might notice and get freaked out.
If Yandere-chan ever lost Senpai's love or if she got rejected by Senpai YandereDev could imagine her crying over it. If Senpai was ever killed and Yandere-chan knew who did the deed, she would feel a cross between deep hatred and total, hollow emptiness. If Senpai ever committed suicide because of Yandere-chan, she would do the same.
Yandere-chan would love to one day confess to Senpai under The Cherry Tree.
In the first intro Yandere-chan is just a love-hungry schoolgirl, so she has every right to be disgusted by Info-chan. Yandere-chan can choose to be moved by what Info-chan says and can do things that way. In the second intro Yandere-chan is less moral, but still doesn't have to be evil, so she is also not pleased by Info-chan, but can still choose to do bad things. Yandere-chan has the ability to not help Info-chan by not taking panty shots or killing others.
Yandere-chan's only current ally is Info-chan.
It's a huge spoiler to say what would happen if Yandere-chan didn't take panty shots or kill students, which would help Info-chan. YandereDev wants it to influence some events near the end of the story.
Info-chan's attitude towards or beliefs about Yandere-chan may be affected by the player's actions.
Yandere-chan works 100% solo however her co-operation with Info-chan is the only exception
The rivals will never know that Yandere-chan exists and that they have competition. Yandere-chan is seemingly fine with eliminating them so long as she gets her crush.
Yandere-chan might think that she's better than the rivals because when Yandere-chan saw Osana, she believed that Osana could never love Senpai like she can.
Yandere-chan is indifferent to both her parents. She believes that her mother is a kind, pure, warm, gentle and innocent lady, and the mother loves her daughter dearly because Yandere-chan is a physical manifestation of the love between the two parents. Ryoba knows about her daughter's non-existing emotions.
If she saw Yandere-chan in a relationship , the mother would just be happy to see her daughter had found love.
Yandere-chan is indifferent to both her parents. Her father has suspicions about Yandere-chan, but does not know her true nature. He's a little creeped out by her, but loves Yandere-chan nonetheless. When Yandere-chan noticed that her parents were worrying about her, she started pretending to be normal. Afterwards, there was no longer a reason for her parents to worry about her. If the father sees Yandere-chan trying to romanticize a female Senpai, he would strongly discourage the relationship. His values come from Japanese society, where there is still homophobia in the country. If Yandere-chan was in a hetero-relationship with a male Senpai, the father would worry about the nature of the relationship, and how it began.
Yandere-chan's family isn't so close and once the women have found a male they don't usually spend time with others. Yandere-chan might've not even met most of her relatives. No one is on bad terms though.