Nina

As the daughter of an Irish Koppou and a British Aikido master Nina developed a well-rounded fighting style. She would become a hired assassin and take on a contract to kill Heihachi Mishima in the first King of Iron Fist Tournament.

Ultimately she would fail, but soon after, a new offer, this time to kill Kazuya Mishima, would put her back into the tournament. But this time, it was not just about her work. She had a personal score to settle with her sister Anna.

Nina then succumbed to Mishima and became a test subject for their cryogenic technology. The Ogre's power woke her up 15 years later. Under Ogre's control and without her memories, she became determined to kill Jin Kazama.

After escaping Mishima's grasp, Nina became an assassin for hire. Unable to remember her past, she killed and executed for profit. One such target was Steve Fox, a world boxing champion. The mafia syndicate that had hired her for the job also informed her that he was her son. As she is ready to kill him, she hesitates and is then ambushed by Lei Wulong. While making her escape, she bumps into Steve Fox and shares a short moment before Lei pursues her.

Nina was then able to recall her past, just as she was in the process of seeking out her sister's help. She remembered her rivalry with Anna and signed into the King of Iron Fist to resolve that dispute. Nina then became a bodyguard for Jin Kazama, joining the tournament once more to keep him safe.

Heihachi forced Nina to work for him after defeating her while attempting to find Jin. He convinced Nina to help him find Jin. Eventually, they would find information leading to his whereabouts in the far east. After saving Jin, Nina splits ways with the Mishima Zaibatsu corporation and goes back to working as an assassin.

One of her first jobs is to kill the members of a mafia wedding between an executive of the G Corporation and, as she would find in the middle of the operation, her sister Anna Williams. She then sneaked into the bride's room and stole the wedding dress, using it to infiltrate the wedding and killing all her targets in a storm of bullets. A storm that would catch the attention of the Tekken Force and force her to leave in a hurry.