Quirkless but powerful (BNHA x OP female naruto reader)

Backstory

"I'm sorry, but your daughter...she's quirkless." those simple words changed my life

"You're worthless to me, you're not my daughter!"

"B-but, momma...you said it doesn't matter..."

"Oh, for gods' sakes f/n, did you seriously think that nobody would care if you don't have a quirk? EVERYBODY CARES!"

"P-papa? where are we going?"

"Somewhere far away! brat! and don't call me papa!"

"O-ok..."

"Now...Stay here, die here I don't care, you're not my daughter anymore!" papa- or I guess my biological father left me in a forest, alone I didn't know what to do, I was after all a child

I understood then and there, that I was abandoned because I was weak!

"I know! I should look for a cave to stay that's what explorers and all do in those T.V. shows! For the night I'll stay there, I should also collect some dry sticks with which I can make a fire, and I should collect some berries and fruits for dinner! I'm so smart!" I giggled then, I couldn't help it, it was my nature to smile even if I'm sad as it is even today

I luckily found a cave and stayed there for the night over a week I collected food and supplies and spotted a river too, I made the cave into a livable place, I obviously couldn't hunt anything down except a few rabbits because of my nimble but weak physical body.

I then started training myself doing push-ups and pull-ups (With the help of a tree branch that was low enough to not hurt me if I fell), sit-ups, and running, most of my physical body became strong because of how much I tried catching more food (Fish or wild animals).

After 3 to 4 months I consciously became aware of how strong I had become, but there was no one to pat me on the back, no one to tell me 'good job, little devil.' no, I'd lost that a long time ago.

"You've been working hard, huh, kid?"

"Who's there!?" I picked up a stone dagger I'd sharpened to protect myself

"Calm down, kid. I mean no harm." a black-haired man, who I learned was called Madara Uchiha approached me

"W-what do you want!?" he looked vaguely familiar

"Kid, I've been watching you, you're incredibly resilient and determined to become strong, aren't you?"

"I am."

"How about you come with me? I can teach you."

"Teach me? why would you do that? What's in it for you?"

"The mere fun in it, teaching someone weak to become strong is challenging but possible and I love the challenge."

"You...would teach me....just for....fun?" I slowly, unconsciously became more and more relaxed and dropped my weapon

"Yeah, kid, I would. But it has a cost, of course."

"What is it?"

"You will have to promise me that you will work your hardest, and you will have to become a vessel for the Kyuubi, the nine-tailed fox."

"T-the nine-tailed fox of the myths?"

"He exists, yes."

"I-I...I'll be able to become a hero if I fulfill those two criteria?"

"Yes, yes you will."

"I...ok, but you have to promise me something too."

"What is it?"