Saying that Jubilee has a bubbly personality is like saying that a shaken up soda might contain bubbles - it doesn't go anywhere near far enough. Unfortunately for people around her, Jubilee's on a perpetual caffeine high (well, except for in the morning, because duh, no one likes mornings). She can talk nearly as fast as a speedster, and generally does it in long, nonending sentences - especially if she thinks it's annoying someone she feels like annoying. Not because there's any malice in her - there really isn't - just because some people are fun to annoy.
Authority figures normally fall in that category. And people who think too highly of themselves. And ones who sputter when you chatter at them endlessly. And...yeah. You get the idea.
Jubilee is feisty, and willing to prove that just because she lacks height don't Think she lacks anything else. She's also a loyal, true friend, and will go out of her way to help people who need help. Or who she thinks need help. She's deeper than she seems on the surface, ok?
Jubilee can generate what she calls "pafs", which are energy plasmoids that resemble fireworks. Unlike fireworks, they pack a considerable concussive punch in addition to heat, light, and noise. Or they can, anyway - Jubilee's well aware that she hasn't quite mastered that aspect. Blowing up the dumpsters scared her, and hey. There's nothing wrong with lights and sound (and the occasional fire, afterwards).
Jubilee's a talented gymnast, having competed at the junior level before the death of her parents. She's also very good on roller blades (which yes, she realizes isn't "in" anymore, but whatever, they're awesome) and roller skates.
Shopping. Roller blading, shoplifting, hanging out with friends, other people's powers.
As the only daughter of wealthy immigrants Dr. and Mrs. Lee, Jubilee lived a life of privilege in Beverly Hills - one that she found boring, eschewing more normal pursuits for a hobby of petty theft at the local mall. It was there that her powers manifested; she and her friend CynJen had been using their favorite tactic of shoplifting and making a quick on rollerblades when she found herself cornered by the mall rent-a-cops who'd followed them out of the mall and cornered her in a dead-end alley between stores. Panicked, she fired of a flurry of pafs which destroyed the dumpsters and loading dock.
She confessed to her parents - there wasn't much else she felt she could do - and while they were definitely not okay with her crime spree, they took the news that their daughter was a mutant well. Jubilee settled in to being grounded for the foreseeable future, but it didn't last long. Her parents died in a car crash when she was 12. With her aunt out of the country and incommunicado, Jubilee was shunted into foster care - and decided that despite them being okay people, she wasn't a big fan. After one shouting match with her foster family over a report she'd been shoplifting got a bit out of hand, Jubilee decided that the whole faux family thing wasn't for her. She moved into the mall, surviving by a combination of stealth, shoplifting, and giving shows with her fireworks outside the mall.
That is, until a pair of young girls appeared at the mall through some kind of portal. Intrigued, Jubilee kept a discrete watch - and when they opened another portal to leave, dove through after them.