Sylvia, my character, is a disabled girl who was the victim of a villain attack involving poisonous gas in America, damaging her lungs nearly permanently and causing her to cough up blood. Every drop of blood she gets is valuable to her, so this first arc of the RP is focused on trying to heal Sylvia. After an unexpected attack on the school on the very first day, after Sylvia has replenished her blood, everyone has been moved to the dorms for better protection, and instead of being in Class 1-C, like Sylvia originally was, she was moved to Class 1-A so that the students there could protect her as well as provide experience and stuff. Meanwhile, everyone else has been settling happily into their classes, and Sylvia's older brother, Jack, became the Pro Hero Deku's assistant in teaching Class 1-A, as he's one of the Big 3 of the school. He's a child prodigy with the ability to control the air molecules around him; it's a quirk I call Atmosphere, which means he can control the air and create wind, make it hot or cold, or make different weather conditions (which is the hardest thing for him to do). He's also a kid genius; the whole family is. Sylvia also has a little sister, but now all of them live in the dorms with their adoptive father.
Also they were homeless and all of them are traumatized, but after everything happened, Jack finally realized he's been babying his sister and was overprotective of her, so he tried being lenient and now Sylvia's taking part in the Villain-Hero training with some encouraging words from Deku as his motivation. Now Sylvia's trying to be a Hero like she's been trying for this whole time.
After this arc, Sylvia will be healed, but I don't know what'll happen once that's done.
Sorry this sounds like it's centered all around my character. I feel kinda bad, but after she's done that, all that's really unique about her is that she's literally Deku as a girl with a different quirk, backstory, and appearance, in that she's just as analytical and hardworking as him.