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Osmotic Assimilation

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A ground-shaking rumble filled the concrete halls of the bunker Hisashi Midoriya called his primary base of operations. At 6 foot 2, even with a more lean body type, he cut an impressive figure; with a well tailored suit being his preferred outfit, his presence alone demanded respect.

However, with his gray hair looking like he’d just crawled out of bed, tie horribly tied (it always took him at least 3 tries), shirt untucked, and sporting a mild 5 o’clock shadow, it was jarring to those that knew him to see him so unkempt. The international crime lord known as All-for-One’s careful facade was fractured, and Kurogiri knew it.

“That no good muscle-brained idiot! How the hell did he even find this base?! My information said I had at least 3 years before he found me! Four, if I played my cards right! Kurogiri, how’s young Tomura doing?”

“I’ve gathered all of his things and he’s just in the other room. Do you want me to warp Gigantomachia here? I have his coordinates and am waiting for your order.”

Hisashi finished packing the last of his personal belongings and threw the suitcase at Kurogiri. Thinking for a moment, he shook his head.

“No, actually, I’ve got a more important job for you. If this goes the way I think it will… Machia’s going to be needed elsewhere. Remember these numbers, Kurogiri: 35 degrees, 39 minutes, 13 seconds north. 137 degrees, 25 minutes, 49.1 seconds east. Do you have those numbers memorized?”

Kurogiri gave a short bow. “Yes sir, and what do you want me to do with those?”

Sighing, Hisashi started straightening his appearance.

“You, Shigaraki, and Gigantomachia are to convince the people at that location of their own free will, to get far, far away from Japan. If I’d had the expected three years, I could have ensured their safety by… silencing those who’d seek to harm them in my absence, but it’s too late for that now. The briefcase has a letter that should help.”

The narrowing of the yellow lights of his eyes was the only indication of Kurogiri’s distaste for the wretches his master has had to keep in line. 

“Very well, by your leave I shall get the young master out of here.”

Finally getting his tie properly done and straight, Hisashi pulled a photo out of his pocket:one of him with a young woman with dark green hair, and a toddler with his messy curls and the woman’s hair color.

“You’re free to go Kurogiri, live long, and prosper.”

“Sir, is this really the time for jokes?”

Chuckling, Hisashi let the embers build in the back of his throat.

“I always was partial to gallows humor, old friend.”

Breathing flames onto the photo, he watched as the last of it disappeared into ashes.

If someone were familiar enough with Kurogiri’s unique biology, the droplets of light that disappeared into the air might have been considered tears as he closed the door behind him.

“So, you’re saying he has a hidden quirk?”

Midoriya Inko let out an internal sigh of relief. Though her husband had his secrets, he had let it slip that any of their kids had a high chance of being quirkless. Though hidden quirks weren’t uncommon, there were usually small signs that they existed.

“Yes ma’am. We aren’t quite sure what it is exactly however. The best we can compare it to is an adaptation quirk. His cells are very adaptable, and seem to react to stimulus such as other organic material. We do know however that it is a mutation quirk, not an emitter.”

Petting her sons hair, (so much like his father’s), she couldn’t help the worried thoughts trailing in the back of her mind. She couldn’t be more thankful he’d worn himself out the night before watching the hero news and had fallen asleep while waiting on the results.

“Anything else I need to know doctor? My son wore himself out the night before and my husband was wanting to hear the final verdict as soon as he could. He even told me he’d stay up all night in America if he had to.”

She gave  a soft chuckle thinking of Hisashi pacing back in forth in an american hotel waiting on her call, even if he had important meetings early in the morning.

“No ma’am, that’s all we can say for sure right now. I’d suggest  bringing him in again next year if nothing obvious shows up, or visit a specialized lab if you want to know more. Quirks like this tend to be very slow acting in their infancy, so we might not see anything for a long while and without more extensive testing.”

Bowing to the doctor slightly, she picked up Izuku, careful not to wake him up, 

“In that case, thank you for putting our worries to rest, and have a good day.”

As she got started towards the train station, she managed to fish her cell phone out and dial up Hisashi’s number. Normally he picked up the phone before the third ring, but as it hit voicemail she couldn’t help the spike of worry that pierced her heart.

It wasn’t until they got home that her worries really made themselves known.

Though the purple smokey figure might have been eye catching for a second  to most, the suit he was wearing really held her focus. Her husband only wore the highest quality clothing he could find, and the suit this figure was wearing was the same make. The fact that he stood up from the bench he was sitting on the second he saw her didn’t help, either.

“Mrs. Midoriya I assume?”

The voice was deep, and had an echoy quality to it, even with how quiet he spoke to not wake her son.

“Yes, I am. Why are you asking? And who are you?”

She had managed to fish her keys out and was just about to unlock the door when she heard the words she hadn’t  wanted to hear for another 40 years, and even then they would have been too soon.

“It’s about your husband, ma’am...”

Having carefully set Izuku into bed, Inko headed back to the dining room where she had quietly  asked the man to take a seat. Grabbing the tissues she knew she would be needing shortly, she took a seat across the table from him.

“Y-You’re saying something happened to my husband?”

Kurogiri did his best nod, standard to those who didn’t know him.

“I’m… unsure at the moment, truthfully. How much do you know about your husbands work?”

Dabbing at tears, Inko did her best to recall what all her husband had let slip in their years together.

“I knew h-he was very secretive about it. I knew h-he h-had a lot of meetings, and that some people didn’t like what h-he did.”

Kurogiri let out a sigh at that. He couldn’t blame his boss for not telling his wife, but this would complicate things… quite a bit.

“Midoriya-san. There’s no easy way to say this, but your husband was the king of Japan’s criminal underworld.”

If she were holding something, she’d surely have dropped it in disbelief.

“My h-husband was a WHAT?!”

Covering her mouth, she looked at the door to Izuku’s room to listen for any noises, and relaxed when there weren’t any. Turning back she glared at Kurogiri with teary eyes.

“Now Kurogiri-san, I may be a housewife, but I don’t appreciate some stranger coming in and badmouthing my husband and insinuating that he’s some sort of criminal psychopath!”

Kurogiri was worried this would happen, and carefully,  moving slowly to not scare the poor woman, he dropped a briefcase onto the table, warping it in from where he had left it at their nearby hideaway.

“Hisashi was a good man, that I don’t dispute you on, but I’ve known him for over 30 years, and I can guarantee you, he had his hands in many cookie jars. He wanted me to give this to you.”

Opening the case, Inko saw several of Hisashi’s personal travel items, but on top was an envelope that simply read “I.M”. Pulling it out, she broke the seal to withdraw a letter.


To my angel,

If you are reading this, then I fear something has caused a worst case scenario for me to not be telling you this myself. Chances are, I gave this note to a long-time friend of mine named Kurogiri. He might have a young charge with him named Tomura Shigaraki, depending how much of a hurry he, and by proxy, you must now be in.

I’d hoped this wouldn’t happen for many, many years, but I wrote this as a sort of just in case. The man you knew was not fake in the slightest, but many details of my centuries long life have been kept from you, and not without good reason. I had hoped to keep work and home separate as much as I could.

I didn’t mean to become the crime lord I am, but as the years wore on, I discovered the best way to control crime was to be in charge of it. I do not expect you to approve of my methods, but you can’t deny some of the results. Human trafficking is basically non-existent now, but I have… ‘associates’ who have repeatedly wished to change that, along with several of the other policies I enforced with an iron fist.

If something happens to me, they will come for you, even if they don’t know for sure that you exist,  and I simply can’t take the risk. Get far, far away from our home, I have another that I purchased with enough proxies and relays that no one should be able to find it. I’m so, so sorry you had to find out like this, my love, but I was doing what I thought was best, and even now am  doing what I hope is best for you, and for our son.

With love, H.M/All For One.

By the time she finished reading the letter, her tears were running freely and smearing the once-dried ink.

Kurogiri’s smoky appearance didn’t change as the woman broke down in front of him. But he did push the box of tissues closer within her reach.

Inko slowly managed to get her breathing under control, wiping the streaks from her cheeks.

“Is th-that why you’re here? The sa-safe house he mentioned?”

“Yes, your husband had a bodyguard that he wanted me to have you and your son meet with. However, with the way things unfolded, he also wished for me and my charge to accompany you as well.”

Wiping the tears from her face, Inko felt like the entire world was weighing on her shoulders.

“How quickly do we need to leave?”

“It would be wisest for us to leave within the day; my quirk would let us leave this very moment if it was required.”

Standing up, Inko put the letter back in the case before closing it back closed.

“Give me a few hours to grab everything and get Izuku ready. Don’t mention any of this to him please, I’d rather know for sure before we tell him.”

Standing himself, Kurogiri used his quirk to open a portal against one wall.

“Very well, I’ll be back in 2 hours, as I imagine young Shigaraki is getting hungry. I shall see you then.” And without another word, he was gone.

As the wisps of smoke faded away, Inko began the daunting task of packing the essentials and gathering the resolve to wake up Izuku.