A/N: Overhaul and Mirio's relationship in a nutshell

I wasn't sure how much time has gone by, since Overhaul began his experimentation on me.

But, I know I felt like absolute shit.

I was drenched in sweat from the pain, feeling my chest heaving up and down. My entire body was shaking from fatigue.

On top of that, Overhaul was able to make five bullets, filled with my dna. He planned to use them on the heroes when they stormed the place.

Speaking of the heroes, I haven't heard anything from Nighteye, Eijirou, or Aizawa since I first arrived at the yakuza house.

I had absolutely no idea what was happening on their side.

A knock on the door brought Overhaul out of his maniacal bloodlust for a split moment.

"What?" He simply seethed lowly, impatiently waiting for an answer from the other side of the door.

"Master....we need you now." The man mumbled from the other side of the door.

Overhaul muttered profanities under his breath, counting up the bullets he created from my quirk dna.

"No. I only have five bullets. I need to make at least 8 of them—"

"Sir, there's.....no time." The man simply said, sounding slightly stressed.

Overhaul glared at the door, as if suddenly understanding.

He set the scalpels down, grabbing the five bullets in his hands and shoving them into his pockets.

"Then at least get someone down here to escort Margo to our new hideout spot." Overhaul called out, quickly placing his mask back on his face.

"There is no one to do so. Everyone already has their hands full with their assigned duties. I'm sorry." Overhaul's henchman replied.

I jumped slightly when Overhaul slammed his hands down on my both sides of my head, looking at me angrily.

"Damn it. You're a lot of work and stress......but you're worth it to me." He mumbled to me blankly, before grabbing a gag and a piece of duck tape.

"Wait—" I started protesting before Overhaul shoved the gag in my mouth, practically down my throat, and slapped a piece of duck tape over my mouth.

"I'll be coming back for you, after I escort Eri to our new spot. Feel free to make yourself comfortable. No one, not even those stupid heroes, will find this room of the house. It's been strategically placed. I'll be back for you soon." Overhaul said to me, before briskly walking out without another word.

I heard him locking up the door, five different times, before his footsteps were gone.

I was left alone, strapped to this table. The wounds Overhaul created on me were bleeding everywhere, as he didn't have time to patch me up.

"Margo..." I faintly heard from my earpiece, causing my eyes to widen in surprise.

"Hmm!!!" I called out desperately, muffled from the mouth restraints Overhaul put on me.

"Margo, it's Eijirou. I'm coming for you!" I heard Eijirou yell.

I was completely mortified for him, as I heard a bunch of screaming and crashing in the background, followed by the yells of Fat Gum and Rock Lock.

Everyone must be here.

I tried to speak to Eijirou, with no avail, only being able to give him muffled responses.

"Damn it! You can't speak. That bastard must have done something to you. Listen, there's a tracker on your earpiece. I'm going after you!" Eijirou yelled, before I heard Aizawa.

"Kirishima! Stay together!!—" Aizawa exclaimed, before Nighteye cut him off.

"No! Let him go!! Let him make his own decisions right now! The foresight! The future! Let him go! We will follow you—" Nighteye began saying, when the reception became fuzzy.

"KIRISHIMA!!" Nighteye and Aizawa suddenly screamed, causing my heart to jump up my throat.

What happened?! Why were they screaming his name?!

The contact in my earpiece abruptly cut off, causing me to start screaming.

I was terrified, not hearing Eijirou or anyone else speak.

"M....argo!? Can....hear me?" Eijirou suddenly said, coming back online.

"Eijirou!!!" I screamed out muffled, relieved that he was alive.

"I just got separated from the group. Someone's quirk rearranged the entire building, and I ended up falling further underground. It's just me now. But, it's okay because I think I'm actually closer to your location now. The tracker from your earpiece says I'm getting really close to you." Eijirou explained, sounding slightly out of breath from running.

Not being able to respond, I simply hummed in acknowledgement, helplessly waiting for him to find me.

After a few moments, Eijirou let out an irritated sigh.

"What the hell!? It says you're supposed to be right here!! There's nothing here. No doors, or anything. It's the blank walls and the hallway!!" He exclaimed in frustration.

What!? What the hell happened to the door?! Is he in the right spot?

"Damn it, Margo!! Where the hell did he put you!?" Eijirou spat angrily, slamming his hands on the wall.

Wait a minute.

I heard Eijirou's hands hit the wall. I heard it.

That means, he must be right behind it.

But, what the hell happened to the door? Overhaul, or one of his men must have used their quirk to hide or get rid of it. That way, it wouldn't be visible to the heroes. They'd never find me.

I began thrashing and yelling as loud as I could, hoping he could hear me behind the wall.

I wasn't able to speak and communicate to him my position. I had to hope he would hear me.

He was quiet for a minute, trying to make sense of my screaming through the earpiece.

But, after a moment....

"Wait a minute...." he breathed out.

I heard an ear piercing split ring throughout the room now, along with the sight of debris and dust flying everywhere.

The wall was now broken.

I turned my head as best I could, seeing Eijirou panting slightly from breaking through the wall.

His eyes widened as he spotted me, immediately sprinting over.

"Margo!!" He yelled out, running over to my restrained body.

He quickly peeled the duck tape off my lips, before yanking the gag out of my mouth.

I gasped for air, coughing slightly, as Eijirou quickly undid all of my restraints.

I felt him lift me off the, now bloodied, operating table...pulling me right into his arms.

I squeezed my eyes shut, hugging him back tightly.

"Y-You found me. I-I can't believe you found me." I breathed out into his bare shoulder.

"Of course I found you. You didn't think I'd leave here without ya, right?" He chuckled softly, before pulling away from our hug to assess my injuries.

His eyes trailed over the areas Overhaul worked on me...my shoulder, my thigh, my side. Blood was dripping from my wounds pretty steadily.

"Your injuries, the placement. Just like his foresight said..." Eijirou whispered in awe, taking in the placement of my wounds.

"What?" I asked him in confusion.

Eijirou looked back up at me, before running around the room now.

"Nothing. Come on, we need to find you some bandages."

.......

Eijirou and I began running down the empty, dark hallway now...not sure at all where we should be going.

"Are you sure you can walk okay?" He asked me, hardening his arm in case a surprise attack jumped out at us.

"Yeah, I can walk fine. Everything hurts a little. But, I'm fine. Right now, we just need to find Eri." I called out to him.

Eijirou was about to respond, when the hallway began sliding around up, down, forwards, and backwards.

"Not again!" He groaned out.

Eijirou and I yelled in surprise, falling into each other from the changing equilibrium.

I lost my balance, sliding harshly into the wall.

"What the hell was that?" I groaned out, sloppily shuffling to my feet.

Eijirou quickly got to his feet, too....focusing on me.

"Yeah, that's been happening lately. Someone's quirk must be rearranging the building every couple of minutes. It's probably helping Overhaul get away." He groaned out, coming over to me.

My eyes widened when I heard the cocking of a gun, whipping my head towards the sound.

I looked over, seeing two of Overhaul's men coming towards Eijirou and I.

That's when I realized, the gun was pointed at me.

"You shouldn't be running off like that, Margo! The boss man will be mad. These bullets are made from you, sweetheart! Let's see what they do!!" One of the men exclaimed, shooting the gun at me.

I didn't even have time to react...and apparently, I didn't have too, as I saw Eijirou appear in front of me in an instant.

My jaw dropped when I saw blood fly up from his shoulder, signaling he got shot.

Oh shit!! He was so focused on saving me, he didn't even have time to harden himself!!!

He grit his teeth in pain, stumbling slightly from the hit he took. His quirk was activated now, but it was too late. He already got hit.

"Eijirou!! Are you okay!?" I screamed, helping him to gain his balance.

He groaned slightly, before sloppily shuffling back to his feet fully.

"Yeah, I'm okay. You didn't get hit, did you?" He asked quickly.

"No." I sighed out, relieved that he was okay.

Those bullets contained my quirk dna, and Eijirou just got hit with one.

But, luckily....my quirk doesn't work on him for some reason—

Eijirou was about to speak again, before his eyes widened in shocked pain.

He inhaled sharply, before clutching his shoulder and dropping limp to the floor.

"Eijirou!? Eijirou!?! Look at me!!!" I exclaimed, dropping to my knees to look at him.

"Aghhh!!! It h-hurts!! So bad!!! E-Everything hurts!!! What's h-happening!??" He choked out, clutching his side, then his head, then his legs.

I furrowed my brows in panicked confusion, not understanding what was happening. Is this quirk bullet, that contains my dna, affecting him!?

I thought he was immune to my quirk!!

"Eijirou...I think....y-you're experiencing the effects of my quirk...." I called out in confusion, starting to become overwhelmed with his pained screams.

I felt horrible.

I saw Overhaul's men walking towards me and Eijirou now, smirking proudly.

"Damn, that bullet works great. Yeah, the boss is a smart man. Once he found out that your quirk doesn't work on certain people, Margo, he attributed that to the fact that your quirk simply can't pierce into the body. He hypothesized that if your quirk dna is injected directly into the bloodstream, then it can work on anybody." The henchman explained, looking at Eijirou's slumped body with satisfaction. 

Millions of questions arose in my mind, from the henchman's words. Number one, how does Overhaul know my quirk doesn't work on certain people? I never told him that. The only people I told, were the heroes I trusted, my classmates, and Shigaraki, accidentally.

Number two, this means that Eijirou isn't completely immune to my quirk, the way we thought he was. It seems that while my quirk won't work on him, naturally....if it is directly injected into his body, it affects him, the same way it does everyone else.

This further affirms that Eijirou's hardening quirk genetic is able to offset my own quirk genetics, somehow. But, since the bullet injection broke through that barrier, now my dna is able enter his body freely.

"Let's take them both. We can show the boss the effects this girl's quirk bullet had on this red haired boy. He's supposed to be one of the people her quirk doesn't work on. He'll be satisfied to see these results." One of the men said, gesturing to Eijirou's vulnerable, tortured body.

Once again, I never told Overhaul that Eijirou was the one who's immune to my quirk. How does he know this information?

But, even so. These men want to take Eijirou. That's what they're saying.

I took in their words, feeling something snap inside me.

I felt my eyes darken, as I slowly stood up....stepping in front of Eijirou's slumped body.

There's no way in hell I am letting them touch Eijirou.

I glared at the men, pulling out two daggers from my suit.

"If you want him, you'll have to go through me, first." I stated lowly.

Eijirou, you've protected me so much. Now, it's my turn to protect you.