*Information as of May 1995

She doesn't remember much of her life before middle school, but she knows she, her twin brother Ken, and their mother moved from Japan to Bakersfield when she was a toddler. When she started middle school, she was immediately met by a trio of seniors who picked on her for her accent. It was horrible until a wolf freshman intervened by shoulder ramming them like bowling pins. A fight ensues for about 30 seconds until a staff member broke them up. She tried to explain what happened, but the staff brushed her off and tell her to go to class. Although she felt lost afterwards, seeing the wolf from time to time somehow gives her a safe and comforting feeling. The whole experience even changed her. throughout the years she started developing a tomboyish and rebellious attitude and grew a taste for the action genre. Heck, watching all those movies and cartoons somehow help her nail down an American accent. She was getting troublesome that her mother disciplines her by teaching her some martial arts and sending her to her uncle in Japan every summer and winter for more training (until he went to jail in winter '94). Nearly a week after Daniel's disappearance, JEN took one last opportunity to make mischief at a school assembly before secretly leaving for Santa Azul to find him.

JEN's fighting style is known as Takuro-ken, a form of Karate that mixes in elements of Jeet Kune Do. Like Daniel, she has the Rage, but her powers is an unorthodox form of fire abilities, like combusting her hands, throwing "cherry bombs" that sticks and detonates by her will, and heating and manipulating metal, but she mainly uses it to form a burning hot sword known as Masamune.