Voice of Steel Rewrite (Tetsutetsu x oc)

Prologue

???'s pov

I sat in the doctor's office next to dad. I stopped listening after a while. I still hadn't developed my quirk and I was 8 now. I didn't understand. Hitoshi and Tamaki both already had there quirks and I had the right genetic mutations for my quirk. It just wasn't manifesting. I ran a finger over my ear and pouted slightly.
"Have you got any knowledge on what her quirk could possibly be? Any information on quirk inheritance from her parents?" the doctor asks, looking towards me.
"No. We never met them and there was no information on any parents in her documentation" dad objects, looking towards me while his glasses slipped down his nose slightly. The doctor walked over to me and started looking me over.
"Its certainly not a mutation quirk. Otherwise it would have shown by now" he states, circling me. 
"Have you noticed any unusual signs of a quirk?" he asks. Dad shakes his head. 
"Well, either she's a late bloomer or you just haven't found what her quirk is yet" he explains. Dad sighs.
"Thanks" he says before taking my hand and leading me out of the room. 
"Dad? Is there something wrong with me?" I ask once we're in the car.
"Of course not. Its not your fault that we haven't found your quirk yet. It'll come eventually" he explains, reversing the car out of the parking space. I bent forward, picking up my book and opening it to the page where I left off. It was fun to read about the mythical creatures in the books, even if they weren't around now. We reached home and I got out of the car, carrying my book with me. I ran over to the table and got into my chair, dumping the book onto the table next to Hitoshi and Tamaki who were bickering about food again. Well, it was more Hitoshi was yelling at Tamaki for stealing something from his plate and Tamaki apologizing profusely. Dad gave me a look after he had been speaking with dad but didn't say anything. I blinked before opening my book again. 

****

I was in the bathroom, waiting for the bath water to fill up. It finished and I stuck my hand in to test the temperature. Suddenly I fell to the floor, hitting it hard. I groan, looking up to try and figure out what tripped me. No one was there. I turned around to see what happened and screamed in response. What happened to my legs. Why was there a tail in their place. I looked over myself. I had scales running up my arms which glittered in the light a soft rainbow. I looked behind me where there were two sets of large fins that protruded from my back almost like wings. The door to the bathroom slammed open.
"I heard someone scream. What happened?" Dad demanded before he looked down at me. His only response was to blink, glasses slipping down his nose.
"Hi dad" I mumble, the fish tail flicking.
"Oh my-Miyoshi. Your quirk" he ran over and pulled me into a hug. Wait. My quirk. I had some kind of mermaid quirk. Cool.
"Now I just need to figure out how to turn back" I laugh.

****

I sat at the kitchen table with my brothers, opposite dad. I just needed dad to come down so I could tell them all. I was fiddling with my fingers, staring down at my lap. Would they all be mad if I told them. I heard loud footsteps as dad ran down the stairs, brushing his hair as he whistled.
"So how about breakfast?" he half sings, putting the brush down and walking to the cooker. 
"A-actually, I wanted to say something first" I object, not making eye contact with anyone. Dad seemed to pick up on something in the atmosphere since he proceeded to sit down, a serious look plastered on his face. All of them were waiting for me to speak.
"I..........I don't like it when you call me she her" I start, biting my lip. Please don't hate me, please don't hate me.
"Continue" Dad states in his usual tired voice. 
"W-well, I'm........ I would prefer if you call me Miura and use they them and he him pronouns....... If that's all right" I explain, pulling my fingers and looking down.
"Why wouldn't it be?" Hitoshi asks, raising an eyebrow.
"Well. I just thought you wouldn't be accepting of me-"
"Our dads are gay, so am I and Tamaki is Bi, why wouldn't we" 
"I'm also pan. Thought it would be good to come out all the way I guess" I smile nervously. Dad places a hand on my head, ruffling my hair.
"No issue there kiddo. We still love you" he smiles, getting to his feet.
"Now how about eggs for breakfast"