Yandere-chan

Yandere-chan is the protagonist and the playable character of Yandere Simulator.

At the beginning of the game, she has a dream about Senpai. That morning, she runs into him as she is running late for school - and becomes obsessed with him. Nothing and no one will stop her from having him. She then sees him being scolded by his childhood friend, a tsundere named Osana Najimi, and plans to get rid of her. (This cutscene is no longer in the present game.)

Every week, a new rival appears - one that the player must find and deal with before the week is up, or else they will confess their love to Senpai and Yandere-chan will be heartbroken and lose him forever.

Appearance
Yandere-chan has fair skin, black hair and grey-black eyes. In her default uniform, 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.

There used to be an Easter Egg where if she ran behind the tree on the side of the school she would be wearing a red and black version of the default uniform. This, however, was removed, after being reported countless times as a 'bug'.

There are several other Easter Eggs such as Punished Mode, Slender Mode, Bancho Mode, Hateful Mode, Titan Mode, Galo Mode, DK Mode, Bad Romance Mode and 47 Mode.

Personality
Yandere-chan is, as in the name, a yandere, one who will go to any lengths, even murder, for her love.

In an early version of the intro cutscenes, 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.

Background
Yandere-chan, apparently, has some history with being a yandere. In the aforementioned early version of the intro cutscene, Info-chan mentions this twice, saying "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.

Also, in the post "Halloween and DLC" from the Yandere Simulator blog, it was said that Yandere-chan's mother was a yandere girl while in high school, and killed a girl.

In the current build, if you go in one of the female toilets and take a picture, you can see the girl. In older versions, this can be seen by taking a picture at the back of a tree at the back of the school. There used to be an old easter egg where you run into the phantom girl, and Yandere-chan's uniform will change, but it has been removed as said before. The girl will look at Yandere-chan where ever she goes.

Trivia

 * Yandere-chan's teacher is Rino Fuka and her classroom is 2-1.
 * Currently there are nine different Easter Egg modes for Yandere-Chan.
 * Yandere-chan's birthday is April 1st.
 * While this game takes place, Yonder-Chan's parents are out of the country.