Bupa is a farmer, a breeder, and a hunter, born and raised in the tiny village of Baoshan (stone village (a real place in China)).
She has four children, two girls and two boys, and a niece she takes care of. They are literally the only people she cares deeply for.
She is a firebender who has developed unusual firebending techniques such as heat-seeking (to find animals) and raising and lowering the temperature by controlling the heat in an environment.
Bupa and her husband train hand-to-hand combat techniques together, using any spare money they can scrape together to buy scrolls, teaching each other what they think they need to know to protect their family. They pass their teachings onto their children.
Bupa is straight-forward, ambitious, rude, restrained, very patient, ignorant (due to isolation and access to good education), a quick study, observant, quiet, calculating, focused, honest, angry, emotionally detached from other people, including her husband, and fearless to the point of being reckless. She has been described as being “coldly efficient”, "unsympathetic", and “mean”. She lacks refinement which is to be expected since she has lived as a poor farmer her entire life.
Bupa believes that her children are destined for greatness-that they will change the world and every thing and everyone in it. She quietly works to make sure they get the opportunity to make that happen. This endeavor to raise her children to a greatness that could only be rivaled by the deeds of someone like the Avatar is an all-consuming obsession.
Like so many poor and neglected people, Bupa's loyalty will easily swing toward a Fire Lord-any Fire Lord-who is more concerned with making good social policy than continuing the war.
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A TIMELINE OF IMPORTANT EVENTS
Bupa was born twenty four years ago to two poor farmers.
When she was nine, she was arrested by an army captain for stealing food from a depot. But his general allowed her to work off her debt, realizing the reason she probably stole was due to hunger. He also gave her some firebending lessons in the hopes she would be able to get work with her firebending, and got her father a job as a factory worker. Her mother become a servant in his home. But Bupa was restless and bored and continued to get arrested by the captain.
When she was eleven, after her sixth arrest and pardon by the general, at the wish of her parents, the general sent her away to a school for bad children (a behavior school) where she got into many fights.
When she was twelve, she was expelled from the school and told that she was a deviant and completely incorrigible. She proudly agreed.
When she was thirteen, she met Kei Ben, a twelve year old homeless orphan who proved capable of surviving on his own, and the only person who could make her smile.
When she was fourteen, she had her daughter, Zhen Gui, and she and Kei Ben got married and formally started their family. It would have been considered dishonorable for a girl to become pregnant at such a young age, and for a boy to get her pregnant. But many of the poor people in the Fire Nation are not hung up on their “honor” since it has never served them well. They only care about surviving and moving forward. Plus, it really isn't uncommon for poor people to have children as early as possible.
Over the next five years, Bupa suffered through three miscarries due to poor medical care, over-working herself, and malnutrition.
When she was seventeen, her sister died and she took custody of her nine year old niece, Du Te.
When she was nineteen, a “fancy lady” from the 5th House visited her, offering her a large sum of money to by her farmland so she could turn it, along with the rest of the valley, into a wildlife preserve. But Bupa didn't want money. She and Ren Ci agreed that Bupa's daughter would receive a proper education and that she and her husband would work on the preserve. Ren Ci also agreed to help with medical expenses so Bupa and Kai Ben could continue to (hopefully) have healthy children.
When she was twenty, she had her twin sons, Shi Li and Ying.
When she was twenty three, she had her daughter, Kui.
This is an under-developed bio. She's pretty important to the story. I'd have to give out a lot of spoilers to complete it. -_-;