Well, they say a picture's worth a thousand words, so...have at it
. One distinguishing feature is that the lower half of her left leg has a big ugly scar on it from when a Sharpedo bit her.
Ravenna has a lot of influence from her older brother. First and foremost, she's very honest, both to others and - more importantly - herself. She loves Pokemon of all types and varieties (except for Sharpedo, which she's terrified of) with general equality, and is always looking forward to seeing a battle. The exception to this rule is any Pokemon of the Water type, around which she gets uneasy and nervous. Probably because of her brother's influence, Ravenna loves the Dark type more than any other, and believes they have a unique variety not known to other types. Her favorite species is Houndoom, because she senses a sort of loyalty in it. Ravenna has always been one for loyalty, and hates being betrayed or tricked. Maybe her unconditional honesty with others has something to do with that.
As far as battles go - now that she's got her own Pokemon - Ravenna is always ecstatic to start the next one. She aspires to be like her brother and challenge, defeat, and maybe even join the Elite Four. Her brother is the person she looks up to the most in the world, and she likes the different species on his team because seeing them reminds her of him. Her strategy is also like his: all-out offense with no concern for stat alteration, status impairments, or other such things. Just pure attack power, though she's kind of reckless when she gets excited. Add to her being very excitable, and it's a venerable recipe for disaster sometimes. At least she's often willing to help others recover from whatever damage she may cause when she gets too excited.
Ravenna has lived in Unova her entire life, surrounded by trainers and Pokemon. Her birthplace at the most specific level was Virbank City, which was also where her older brother was born. He was a big part of her life, and his name is Flit Angelo. Flit was and still is the biggest influence in Ravenna's life, guiding her in life through school, hardships, poor health, and whatever else decided to rear its ugly head. Ravenna also used to be a good swimmer, though not as fit as her brother and as such, not really as good a swimmer as him. Sometimes he'd take her to Undella Bay on the back of his Honchkrow, and the two would go swimming together. For a good ten years, Ravenna really loved the water and being in it. Until something happened in the water that changed her opinion quite fast.
Nobody's quite sure where it came from, but a wild Sharpedo had made its way to where Flit and Ravenna were swimming, and attacked the latter of the two. Granted, it was quickly driven off by Flit's team of Pokemon, but that didn't subtract from her pain or injury at all. She spent a week in the hospital while her leg healed, and a few days afterwards in physical therapy to make sure she wouldn't need any assistance walking. But she did get out, albeit with a slight limp from her injury. While she was in the hospital, Flit had a good week and a half to train harder than usual and find new Pokemon to add to a list of species he'd wrestled hand-to-hand, with Flit's dream being to wrestle every species known to man. Except he didn't do any of that; he stayed in the hospital. Not long after Ravenna got out of there, she got a ride on Flit's Honchkrow up to Victory Road. She still had no Pokemon, but he wanted to show her what he did from day to day as a member of the Elite Four (at that time.) She was awestruck. From that moment, Ravenna Angelo wanted to be a trainer; not a swimmer. She could barely swim anymore anyway, for fear of another Sharpedo attack.
Well, the years ticked by and by, but Ravenna didn't get a Pokemon. A few months after Flit showed her his Elite Four job, he left them to teach Ravenna what he knew about Pokemon. You'd be surprised how little Ravenna learned in seven years, short of types and names of most species. Over the course of time, Flit began releasing his team to finalize his decision of retiring. First was his Sableye, then Tyranitar. Following them was his own Sharpedo (much to Ravenna's relief) and Honchkrow, then finally Houndoom left the team. All that remained was his Absol, who refused to become Ravenna's Pokemon. So the years continued on like this, with Ravenna remaining without a Pokemon, Flit being retired from Pokemon battles, and the days being pretty peaceful. Until the two were told Ravenna was being given a Pokemon if she could get to Nuvema Town. The two took off immediately afterwards.