JJ is a character that originated from Scott Cawthon's game FNaF 2.
Role in franchise
She has no hostile role in any FNaF game, and she only appears as an easter egg in one canon FNaF game, that is FNaF 2.
Role in Five nights at Freddy's - The Stories
JJ was made by Freddy Fazbear and Puppet as Balloon Boy's friend in the episode of Season 1 titled Bad Balloon Boy. JJ was never an important role in the series, just a sidekick like Balloon Boy. She was sliced by the Nightmares, just like Balloon Boy