Osana Najimi

'''Osana Najimi is the first introduced rival and a student at Akademi High. She will be used as a tutorial at the beginning of the full game. '''

She was going to be implemented within several months (as of January 11, 2016) according to Druelbozo. YandereDev first needs to complete several key game features before implementing her.

It should be noted that the character who stands under the cherry tree southwest of the plaza is Rival-chan. The original design for Osana had Rival-chan's appearance, but YandereDev thought she didn't look "tsundere" enough. There is now a new appearance for Osana. Rival-chan is the student with the original model, who is now considered a different character.

Original
Osana's original look was Rival-chan's current appearance. She had orange eyes and her hair tied up in two short golden-orange pigtails. Osana's hair was tied up in two pink scrunchies with white polka dots and she had a purple bow on the right side of her head. She wore white leg warmers.

Current
Osana's current appearance has long, orange twin-tails that reach her knees. The ends of her hair fade into a small yellow gradient. Her hair is tied up in thin salmon pink scrunchies with white polka dots, and matching stockings. Her shoes are black. She wears a small red bow headband on the right side of her head. She has a bust size of 1.

As of the March 15th, 2018 Build, her hair and eyes are much lighter and her hair gradient starts further up. This appearance was mistakingly made available to players. As of the March 31st, 2018 Build, she has retained her lighter hair and eyes but slightly less saturated.YandereDev stated that this happened because he wanted to test out features.

Description
"Osana and Senpai have been close friends ever since they were very young children. They have always lived next-door to each other, and have always walked to school together.

Despite their closeness, Osana is quite rude and harsh towards Senpai; she is always easily irritated and quick to anger when he is around. The reason for this behavior is because Osana has developed romantic feelings for Senpai, but she is afraid of letting him know how she truly feels about him.

She doesn't want him to know how she really feels about him, so she is mean to him at almost every opportunity. However, her true desire is to confess her feelings to him underneath the cherry tree behind the school...and if nothing stops her, that day will come very soon."

Introductions
In the original introduction of the game, after Yandere-chan bumps into Senpai, she can be seen talking to him, acting like a stereotypical tsundere. The first intro can be seen on YandereDev's YouTube channel, but this is now very outdated.

In the second intro added in the August 15th, 2015 Build, Osana is mentioned by Info-chan, as she requests for Yandere-chan to murder Osana. Info-chan expresses that she wants Yandere-chan to "make her suffer". It is currently unknown what grudge Info-chan holds against Osana.

Personality
Osana Najimi is a tsundere, meaning that she is hostile and cold towards someone before eventually warming up and becoming sweeter. Regardless of Osana's rudeness and Senpai's ignorance, Osana is still very considerate.

Routine
Though it is unknown at the moment, YandereDev has said that her routine will put her in close proximity to Senpai or other students.

If Osana was put into the game via changing file names in the October 16th update, she would go to the roof, take a phone call, go to the roof, go to class 3-2, and stand there at the back for the rest of the day. She wouldn't take the phone call on Monday.

If she was put into the game via changing the file names in the November 15th update, she would stand in front of Senpai looking at the fountain, take a phone call, go back to the fountain, go to class 2-1, and sit down for the rest of the day.

As of the January 3rd, 2017 Build, it was no longer possible to add Osana into the game via the JSON folder. If the player attempted to add Osana, they will encounter Fun Girl instead.

As of the March 31st, 2018 Build, if added to the game, she will socialize with the Mysterious Obstacle every day and take a phone call on Monday.

As of the May 3rd, 2018 Build, if added to the game, she will socialize with the Mysterious Obstacle every day, and will not take her phone call, nor will she patrol clubrooms.

Senpai

 * Main Article: Senpai

Osana and Senpai are very close, they are childhood friends and regularly spend time together, meeting together in the morning every day, Osana has a crush on him but he is oblivious, as a result, she tries to impress him in the days leading up to her confession.

Osana, Senpai, and Hanako all played together when they were younger. Osana has a crush on him, although he does not seem to be aware of it.

If Osana entered a relationship with Senpai she would give him "tough love" and would lecture him about leading a carefree life and would encourage him to pursue a career that involves one of his interests. This would eventually lead him to become an author or a horticulturalist.

Info-chan

 * Main Article: Info-chan

The second intro does not state why Info-chan is going against Osana. Info-chan simply wants Osana to suffer, suggesting a relationship between the two.

Hanako Yamada

 * Main Article: Hanako Yamada

Osana, Senpai, and Hanako played together as children. Osana might be the only person that Hanako would be willing to "give" Senpai to. Hanako wouldn't really look at Osana as competition, or a threat, or an enemy. Hanako would be very sad if Osana died.

Suitor

 * Main Article: Suitors

In the future, Yandere-chan can matchmake Osana with her suitor.

Trivia

 * Her name osana (幼) means "young child", while her surname najimi (なじみ) means "old friend" in English. Her name and surname osananajimi (幼なじみ) together mean "childhood friend" in English.
 * The word Osananajimi is also a Japanese term for common trope in the romance genre, that is characterized by the fact that one of both childhood friends falls in love in the other. Another term for this common trope is Childhood Friend Romance and for the character type which is Osana is the term Patient Childhood Love Interest.
 * In the final game, Osana may tease Senpai about how he stands under the cherry blossoms all day, a reference to how long Rival-chan was under the cherry tree.
 * YandereDev said on Twitter that Osana's birthday will be in January, most likely the 1st.
 * Osana will perform the same "hip sway" animation as "Sansdere-chan" from Bad Time Mode.
 * The animation can be found with the name "TsunIdle".
 * She is the second tsundere character to be introduced by YandereDev, the first being Tsundere-chan from Kuudere Simulator. YandereDev has said that Osana Najimi is "Tsundere-chan with an actual design that had effort put into it."
 * At one point, YandereDev considered splitting Osana into two characters - a gentle childhood friend with Rival-chan's appearance, and a tsundere childhood friend. They wouldn't have been sisters, however, as that would mean eliminating one might affect the other so strongly that she couldn't consider dating.
 * Her voice actress, Brittany Lauda, plays another tsundere named Audrey from the popular adult game HuniePop.
 * Brittany Lauda was once asked to record more lines for a Senpai-Rival interaction event.
 * Osana's design was inspired by anime characters such as Asuka Langley Sohryu from Neon Genesis Evangelion, Rin Tosaka from Fate/stay night, and her twintails and stockings were inspired by Michiru Matsushima from The Fruit of Grisaia.
 * YandereDev had stated that in a few months, Osana will be added to the game to test out elimination methods that can only be used on "real" rivals.
 * YandereDev said that the fastest possible way to put Osana into the game would be to take all of the code that applies to Kokona and point it at Osana.
 * In the October 16th update, it is possible to add Osana to the game by changing ID 33's name from "Unknown" to random words in the JSON file.
 * As of the January 3rd, 2017 Build, it is no longer possible to add Osana by editing the ID 33's in JSON files. Attempting to do so will trigger an Easter egg involving Fun Girl.
 * As of the August 18, 2018 build, her student ID has been changed to 11.
 * Osana is an only child.
 * She and Senpai attended the same middle school.
 * Her "trademark" color is "probably" orange, but her favorite color is pink.
 * If all the rivals were in school in the same week, Osana would probably end up with Senpai.
 * YandereDev doesn't imagine her mother to be tsundere.
 * On the Yandere Simulator Webpage in the FAQ, Yanderedev said that Osana will be released in either late 2018 or early 2019.  In his "Light Music Club and Guidance Counselor in Yandere Simulator " video, Yanderedev said that only a few things need to be implemented before Osana is implemented into the game.

Quotes