Kuu Dere/True Ending Fanon

Kuu Dere is the main character of the game, Kuudere Simulator (2077).

Story
Kuu Dere is an orphan who found herself homeless at a very young age. She was picked off of the streets by Saikou Corp to be used in a series of experiments involving Potential. She was raised mainly by Yoshiro Ishikawa, a scientist who she looked up to as a father figure, while Ishikawa viewed her only as his favorite test subject.

Believing that the strong emotions it produced would generate Potential, Ishikawa subjected her to harsh conditions, including being forced to fight her fellow test subjects. While his hypothesis proved to be correct, Ishikawa was not satisfied with the rate of which Potential was created.

In an effort to increase the rate in which she produced Potential, Ishikawa had a shard of solid Potential placed inside her chest cavity. While this proved to create more Potential, it also had an unforeseen side effect - a second soul was born within Kuu, referred to as Tsun Dere.

Ishikawa took interest in Tsun, namely due to the fact that Potential production was only increased when she was active. However, Tsun did not look up to Ishikawa in the same way that Kuu did, as she saw through his manipulative tactics, and proved to be an uncooperative subject. Eventually, Tsun attempted to kill Ishikawa for his mistreatment of Kuu.

Ishikawa ran another experiment in an attempt to erase Tsun from Kuu's body while transferring her Potential producing abilities to Kuu. However, the experiment was deemed a failure as it placed Kuu in a vegetative state. Ishikawa placed Kuu in a hospital indefinitely, hoping to one day revive her in order to continue the experiments.

Kuu Dere wakes up in her hospital bed a few years after Ishikawa's death, and interprets Ishikawa's actions as him throwing her away after she outlived her usefulness.

Trivia

 * Kuu wields dual swords, and has given both of them names. One is named Apathy, while the other is named Lethargy.