After accepting a mission from the Union of Nations forces that piqued her curiosity, the kunoichi Kunimitsu went undercover as a student at Mishima Polytechnical School in order to dig for information on the Mishima Zaibatsu.

Kunimitsu played the part of an honor student well, earning the position of student council vice president in only her second year. With her new privileges, she stealthily obtained administrator access to the school's server where she began scouring data for the whole student body, person by person.

While searching, she stumbled upon a student by the name of "Reina Yaotome," which she suspected was a pseudonym. At that exact moment, Reina appeared, almost as if she had been waiting for that moment.

What are you sneaking around for, Miss Vice President? Or should I say "the infamous thief, Kunimitsu?"

I'm not sure what you're talking about, Reina Yaotome... Or would you prefer, Reina Mishima?

In the next instant, both girls had brought out their deadliest attacks, gauging each other's strengths. Ultimately, they came to the unspoken conclusion that they could use one another.

And so, the two would act as best friends—if only on the surface. In reality, both would walk on a knife's edge, each trying to uncover the other's next move.

Before long, Reina proposed a deal: she would provide intel on the Kuatatou—nine cursed blades into which the head of the Mishima clan had long ago sealed away powerful evil spirits—in exchange for confidential information on G Corp's forces.

With a weakness for rare weapons, Kunimitsu couldn't help but accept. In exchange, she received an ancient document listing the location of the Kuatatou.

After decoding the script, Kunimitsu discovered a hidden path at the Mishimas' main estate (Honmaru), which had burned down one year prior. She followed it and was met by the sight of nine rusted odachi swords, each as tall as she was.

Kunimitsu took the Kuatatou and kept her end of the bargain, leaking G Corp's invasion plans to Reina. In order to restore the blades that had lost their luster, as well as learn a powerful new technique, Kunimitsu headed to the hidden ninja village where her father resided.

Several months pass, and G Corp's forces wreak havoc on New York—just as Kunimitsu's intel said they would. Kazuya Mishima, the mastermind behind it all, declares that The King of Iron Fist Tournament will be held again.

On the list of competitors, Kunimitsu spots a familiar name—Yoshimitsu, her mother's sworn enemy. After praying for her bedridden mother's quick recovery, she quietly leaves the village behind her, carrying with her both the Kuatatou and the new technique she acquired.

Please hold on a little longer, Mother. The cursed blade Yoshimitsu is mine for the taking.