Insert image of Balloon Boy here.
For personality and some minor background, she knows how it's like to have been trained, and she enjoyed her tenure. But now, without a trainer like the one she had last, she's sort of been... rather lax. She knows how to fight and she gets by well enough on her own, but she's sort of been drifting like the balloons she embodies, sort of at the mercy of the wind until someone dares to tug at her string. Mere touch alone won't be enough, it seems, as she's searching for a particular type to be held on to.
As for what happened to her trainer, she's legitimately not sure. The last she heard of him was when she was put into a box and he went off to challenge something "brand new and unknown" with Pokemon who were much better trained than she was.
ZergAlts