Janine is the daughter of Koga, and the new Gym Leader at Fuchsia City. She does, however, leave town on many occasions to perform various jobs/ simulations for anyone with the money to hire her. She was shown in VS. Crobat to be in the middle of such a job, pretending to steal a large pearl to test the security at the Goldenrod Museum. After completing it, she pauses on a rooftop to wonder what she is doing with her life.
Her father, being both a ninja and a member of Team Rocket, had hoped to make her a member as well, both serving their master, Giovanni. But with Koga and Giovanni's disappearance, she was left alone and unguided. Searching for not just her father, but a master, Janine found herself in the same situation as Suicune, whom also was searching for a Trainer in its upcoming battle.
Suddenly, Suicune appeared before Janine, and challenged her with her Crobat. Suicune seemed initially caught off-guard by her tactics, but soon won. Before he left, Janine expressed her desires for finding her own master, just as she felt Suicune was.
Janine later fought against Falkner at the Gym Leaders Challenge. Despite overwhelming attacks, she forfeited the match when she left the battlefield, pursuing who she thought was her father. She never did catch the mysterious person, however, and it is unknown if they will ever meet again.