Izuki Midoriya had learned at the age of four that all men are not created equal, not that the first piece of the statement really applied to Izuki due to the fact that Izuki was a she rather than a he. Like many other kids of her generation, her personal superpower, or Quirk, appeared around the age of four, but it wasn't a flashy one nor a seemingly strong one. The name of her Quirk?
Air Filter. A rather basic Mutant-class Quirk that gave Izuki a set of gill-like organs, located on sides of her neck, that prevented anything harmful from entering her lungs, only letting healthy particles in. Air Filter also made breathing through her nose and mouth redundant, still possible but not as effective as breathing through the gills. X-rays had also revealed that Izuki had lungs that were roughly 1,25 times bigger than the average person her age and size. But other than that, an unusually high aptitude for gymnastics and acrobatics (actually being one of the best in her class in those categories) and the grid shaped gills on the sides of her neck, Izuki might as well have been Quirkless. After all, how was having a built in gas mask useful as a superpower for a superhero? Something that had become a legitimate job over the course of the last hundred years or so.
Unfortunately for Izuki, she was a target of bullying at school, frequently being called useless or pathetic due her (in the eyes of the other students) useless Quirk. Something that led to the girl frequently being depressed about it. That is until the green haired girl, at the age of ten, stumbled upon someone one fateful evening who told her the words she needed to hear to find the spark and ignite a fire. Setting her heart ablaze with the flame of ambition and determination. The evening when Izuki Midoriya met Hebi the Demon.
Izuki had been walking through the old and, at this point, abandoned park where she and her former best friend (now main-bully), Katsuki Bakugou, used to hang out along with Bakugou's goons (as the greenette referred to that boy with reptilian wings and the other one with elongating fingers in her head) when the freckled girl stumbled upon the Demon that would become not only her trainer but also her first proper friend in years. More specifically, the holder of the Air Filter-Quirk stumbled upon the Demon sleeping in an abandoned treehouse that some kids had had made at some point. The only reason why Izuki even noticed the Demon's presence in the park was because of the barefoot footprints in the dirt leading to the treehouse. That and the fact that the occupant of the treehouse was snoring rather loudly in a treehouse that had the old "windows" covered with boards, preventing any sunlight from entering. Which Izuki found a little odd, but didn't really really question it as she had heard of people who's Quirks made them unable to be in the sunlight. Whoever was sleeping in the treehouse must be one of those people. A somewhat sad thing, being unable to be in the sunlight, but what can you do?
Izuki wasn't sure what compelled her to climb up the tree and give the door of the treehouse a knock, but she did so and was greeted by the sound of someone being woken up with a startle. A young woman, based on the sound of the voice.
"Whoever is there, go away!" Shouted the occupant of the treehouse.
"Sorry! I'll leave!" Replied a very nervous Izuki.
"Good! And don't come back!"
"Before I go, can I ask you something?"
"Fine! Just make it quick!"
"Do you think it's possible for someone that doesn't have a useful Quirk to be a hero!?"
"…"
"…"
"…"
"I'll just leave."
"Hold up." Replied the occupant of the treehouse before opening the door of the treehouse, which revealed that the occupant was a young woman who appeared to be in her early to mid-twenties and an albino. She was quite pretty in Izuki's opinion.
"Yes?"
"To answer your question kid, most people would probably say no. That you can't be a hero. I'm not one of those people though. I know of people who fought foes several times more powerful than themselves and won using nothing but skill, training, technique and the right tools. Wanna know the kicker kid?"
"Sure."
"They didn't have any kind of Quirk at all. They were Quirkless."
"Really?"
"Really kid. While I admit that it's been quite nice to have someone to talk to, it's getting really late, kid so you should probably head home."
"Yeah. I should. Mom's without a doubt worried sick. But before I go, can I ask one last thing?"
"Sure."
"Can you tell me more about those people at another time and what's your name?"
"I'd be happy to. And you can call me Hebi. You?"
"I'm Izuki. Izuki Midoriya."
"All right then. See you another time, Midoriya."
