Archive of Our Own ^beta

Chapter Text

Bruce woke up to a much calmer morning than Kudou; which didn't mean much considering that he still woke up in a building full of children, but none of the water pipes burst that day so he didn't have to deal with anyone screaming about their ruined electronics — probably because they already did that the previous day, anyway —.

The first thing he did was take a small shower; just to wash off the sleepiness and wake up a little faster before going on his morning run.

He was about to put the kid's hair in a half up ponytail when all of a sudden his spouse and the kid fucking screamed at him to stop from within the void.

Bruce was never happier to have been standing in the far corner of the changing room than he did then; as he jumped in surprise at the ear piercing screech that only he could hear.

After a minute of them finally relaxing, he was informed that one cannot simply put curly hair in a half up or lazy tall bun, especially when it's still wet, since the hair would get stuck in the hair tie and will end up ripping out a chunk of his scalp if left there for too long.

He had no idea how Yoichi knew this — probably something to do with All for One, since the man had curly hair — but he still listened.

However, he unfortunately only made it half an hour into the morning before he couldn't take it anymore; he needed to do something with the kid's hair; it was longer than his — now that the kid found a way to properly care for it —, and was constantly getting in his eyes, god fuck it.

In the end, Yoichi used Black whip to give him double Dutch braids soon after his second shower.
Which actually looked really good on the kid; it also made his white highlights really stand out, showing another touch of Yoichi — they, including the kid, all collectively agreed not to attribute anything to All for One — in his appearance.

"Oh, Deku-kun, I didn't know you coloured your hair" Uraraka even pointed out during breakfast.

Bruce let out one of the kid's embarrassed laughs and replied "Oh, um, yeah. I don't color it, though. It's just a side effect of my quirk"

And it was true; the white parts of his hair only started appearing a few weeks after he got One for All; it was actually part of how they found out about his biological relation to All for One.

The change in appearance was also a great indicator that ninth was going to be developing a quirk of his own, much like eighth did after inheriting One for All.

"Oh, I see" Uraraka smiled "Well, I think it looks really good on you"

Bruce smiled, knowing that the kid would appreciate the compliment "Thanks"
He didn't blush like ninth would have, but that was to be expected; considering he's still a near three hundred years old married man and did not feel comfortable purposefully blushing at a teenager, even if he was possessing the body of one himself.

He engaged in several more small talks throughout breakfast, ignoring the suspicious glares bomb kid kept sending his way.

The kid was glaring at him like he was something between a villain and a disgrace upon this earth, and Bruce was honestly both disturbed and impressed by his ability to silently ostracize others at such a young age; would've probably even worked on him if he was a teenager.

Their first class was math, taught by Ectoplasm, and unlike Kudou, Bruce actually paid attention to the lessons themselves during their preparation month and knew who he was; he even learned some math along the way.

He also knew that the hero made the kid a little nervous, so he made sure to give a little surprised jump whenever he glared at him for too long during their surprise test.

He probably failed that test, if he was being honest, but at least he got the act right.

The test also meant that they didn't have science class that day, since it took two periods to complete.
Meaning that the next period was P.E.

Warmups were nothing special; they never were; whether it be hero school, regular school or military training; warmups were just that thing that you did to prepare your muscles so that you won't regret being alive that night.

It was the training exercise for that day that was the problem; they didn't have one on one fight like the previous day, or even group fights like he remembered ninth doing a few weeks prior.

No, instead, they had a rescue mission; the kind of training no sane person would ever erase a non destructive quirk over.

He didn't treat it any less seriously, of course; he knew how important rescue and security was, and even when Eraserhead paid more cautious attention to him after he used Black whip to stabilize the ruins, he didn't take the opportunity to do something drastic like he would have done has it been something else.

The Help Us Company actors really liked him, actually.
Which meant he had to act even more embarrassed and blushed when they used him as an example than he would have had he made any intentional mistakes.

That's something that Kudou got better in his acting; making intentional mistakes and feigning ignorance when he could.

Bruce could definitely do that, but when it came to things revolving more so around action and time reliant efficiency, he tended to think on his feet with his good old reliable strategy, rather than the new course of action he was supposed to follow.

They all knew how to pretend; it came with the territory; they can't possess each other if they can't act like each other. Some of them were just better at certain things and aspects than others.

He ended up not getting Eraserhead to use his quirk on him that day, which meant he had to wait until Friday, when they had another P.E lesson, to try again.

Needless to say that that was a disappointment.

He still kept possessing the kid from Wednesday to Friday, mainly because he and the vestiges decided to use this opportunity to see how much more powerful and dominant his quirk would become within the vessel if he stayed there for three days.

They already played back memories from when En possessed Izuku's body for two days, and his quirk flow was so prominent that it actually began to effect his physical appearance in other way than just his eye color.

However it also showed a risk that Yoichi commented on; that the quirk slowly seemed to take stand in the kid's system and was almost bursting out of him by the time they got the kid back.

They wanted to check whether or not the quirks became permanently active when possessing over the course of several days; and Bruce's quirk seemed like the perfect one to test this on, since it was practically just One for All with a twist.

Float was also a good option, and they planned to do it with Nana, too, when it was her turn to test the theory, but for now, it was Bruce who tested it.

Chapter Text

Halfway through the second day, Bruce had already gotten bored; he couldn't communicate with the others outside of the phone and sleep like he usually could, all the lessons he attended were so that ninth's spirit could still learn through the experiment, and he still had to interact with and act like a teenager in front of the kid's class.

Though, he had to say, the kid had a talent for attracting shitty blondes and simps — as En would call them —.

On the one side, he had Bakugou and Monoma bugging and bullying him at every chance they've got.

While on the other side, he had both the Todoroki kid and Uraraka absolutely crushing on him; how did the kid not notice that they both reciprocated his feelings, Bruce had no idea; it was clear as fucking day that they liked him.

In the end, he didn't get involved in that mess of a relationship — for obvious reasons — and instead decided to busy himself with upgrading the One for All phone.

He pulled some more private meetings with eighth than usual — which, in the long run, was probably very suspicious from the perspective of the other staff members — and added several new features while making sure that the black market encryptions remained in place.

He put an automatic voice changer in all their voice messages and calls, just in case they ever forgot to mind their volume.

He implemented a permanent tracking program after they almost lost one of the phones during a training exercise, and made another appointment with ninth's underbelly contact to make sure that it was all functional and didn't allow any outside forces any access to their server.

After the first time Izuku made his illegal connections known — refusing to answer any questions on the matter afterwards —, the vestiges took a deep dive into his memories from before he got One for All.

Apparently, the kid was an informant before he was even a teenager, and even gained a loyal following of small time villains and vigilantes who used his quirk analysis to defeat other gangs and villains; he used the money he got from it to help his mom with payments she was short on — because of course All for One was a piece of shit who didn't even bother leaving his family anything in his will despite having a literal child and apparently being the breadwinner —.

The person who encrypted their devices was a small time information broker who found out about Izuku's identity when he was starting out and decided to help him keep himself a secret after he refused to quit — during a time when he and his mother were nearing unsalvageable debt —.

They became good friends and were now willing to help the kid practically for free, both for the sake of helping a friend and also because they apparently owed him quite the number of favors.

In the meeting, Bruce got a digital wristband that they could wear during training exercises and missions to locate and have easy access to their stuff, as well as earphones and extra, burner — and non-burner, by the sound of it — phones that the contact has given them as an extra freebie; probably having already realized that there were more than two people using them and for a far bigger objective than what ninth told them they would be used for the first time.

But most importantly, he got a USB killer tailored specifically for their devices; so if anyone ever got access to them, it would be easy to just put it in and delete all the information on their server, no matter what device it was from.
He even got one of these USBs that had two connectors; one designed for a normal port and another to be used on a phone; so it truly could be used from any device.

Ninth also gave him an actual script to relay to the contact through eighth, to get them to agree to be on the contact list used by One for All.

Though it was mainly people who owed them favors and had little to no connection to them; meaning that All for One would have had little to no interest in targeting them back when he was alive; a description Izuku's contact didn't really fit into due to their close friendship with him, Bruce had to agree that they were useful, and All for One's followers weren't as big of a threat as the man himself was for the vestiges to outright dismiss the idea.

After a group vote, they've decided to go through with the offer, and the encryptor became one of their official contacts; though they did make it clear that they were doing it more so out of curiosity and favors rather than the goodness of their heart.

They wanted to know who they were, and with them all being very careful about what they put on these devices — sticking to only essential yet non revealing information and contacts —, the only way they could figure that out would be if they stuck around; a game — challenge of mystery — that the vestiges gladly accepted with how talented and useful the person was.

They weren't fools, however, and knew that they'd now have to be even more careful than before about what they write to one another on the messages and what information they put on the devices.

The contact agreed not to meddle in or touch their resources and property, and they always made sure to put enough security on everything that even if others knew where their safe houses are located or where their money is, they'd still need a lot more than just that to gain access to them — All for One being the main reason for that caution —, but that didn't mean that they should rely on past safeguards to defend them in this situation.

Once they got back to Toshinori's home, taking the laptop and server with them, they made sure that none of their actual passwords were saved and all their locations were written in their own encryption — a code they've honestly created out of boredom after spending the first few decades in the void and eventually ended up using to further evade All for One.

Fortunately, they were already careful before and only needed to remove a few possibly incriminating things before adding the hacker's details to their contact list — the living ones, that is; they actually remembered to update it this time —.

He couldn't sleep in eighth's house, which was a shame because he already had a guest room dedicated to the kid and his house was so much quieter and felt so much more comfortable than the dorms.

But unfortunately, as they both knew, his identity may be a secret from the press but not from Nedzu, and the principal was already suspicious enough of All-Might and Midoriya's relationship when Toshinori would take Izuku aside for tea and lunch during school, that they didn't want to risk it with him spying on them through their phones.

Toshinori drove him to the dorms that day, or rather that night.

It was really nice having the time to enjoy being together outside the void without having to worry about the luming threat over their heads all the time.

He thanked Toshinori as he left the car, arriving soon after dinner was over in the dorms; which was fine; he already ate at Toshinori's house.

He just hoped no one saw him leaving the car; he didn't want the man to receive any trouble for being close with his successor.
They didn't need a repeat of En and Nana's experience.

Chapter Text

Finally, on Friday, Bruce got his second chance to challenge erasure.

He woke up early, as the kid always did, still not entirely used to going back to sleeping in the first place, even if he was just returning to the void; he hadn't slept in over two centuries; it was weird coming back to it after so long.

First period was Math, again.
And again he just went through class mostly ignored.

The second period was P.E. Finally, what he'd been waiting for.

This time, the training exercise was quirkless duels, and ninth was paired with Bakugo, the bomb kid; the one who very easily could spook ninth into accidentally using his quirk.

It couldn't have been more perfect.

The only downside was that, because it was quirkless one on one duels, they each had to fight one another individually, at different times; which meant that he had to wait quite a bit before he was able to get on the field.

The point of the exercise was to find a strategy and fight without relying on their quirks.

Eraserhead stood to the side of every pair and, as soon as one of them activated their quirk, he deleted it and benched them, having the two wait until another rotation of pairs was through before they could try again.

All Bruce had to do was use his quirk before bomb kid got too angry and used his own first.

It wouldn't have even been that out of place, either; as a lot of students struggled with the concept of restraining their quirks during an exercise where they used to rely on them during before.

Finally, it was his and Bakugo's turn.

They had about fifteen minutes of normal sparring before Bruce's — ninth's — limbs began to glow with Fa-Jin energy.

Eraserhead clocked it right away, but much to his — and Bruce's — surprise, the energy didn't stay in the limbs, or even dissipate. Instead, it burst out, hitting Bakugo with his next punch using the energy he's accumulated thus far.

This time, unlike with Kudou, Bruce's shared confusion with Eraserhead was actually genuine as he flexed his palms in an attempt to make sense of the situation.

Erasure was still active and focused on him, and his quirk still seemed to work just fine; so why was he feeling like it could store so little now; why did it feel as though his muscles would explode if he didn't let out that surge of energy.

Eventually, after Bakugo stood up and Eraserhead shifted his attention towards him, Bruce came to the conclusion that, much like with Gearshift, erasure stripped Fa-Jin down to its base form; the same form it had before its first ever awakening.

Back when he was younger, his quirk could only store small amounts of energy before he was forced to release it; the one time he didn't led to an extended visit to the hospital and a lecture from his very poor mother.

They didn't know about the concept of quirk awakenings back then, but as he grew up, he felt his meta ability begin to develop and allow him to store more energy in his muscles without it overwhelming his body.

He could only assume that erasure erased that progress and reverted his quirk to what it was before that development.

He was about to return to the benches after Bakugo has calmed down when something stopped him.

As Danger sense returned to his mind, Bruce turned to look at Aizawa as the man observed him with suspicion, like he doubted the functionality of his own quirk, or perhaps it was the nature of ninth's.

Either way, it wasn't good for someone to have suspicions of the kid; because suspicion meant them looking in, and that could lead to trouble; especially if it was someone as resourceful as Eraserhead; and especially if he had connections to someone like the rat, who was even more so resourceful and intelligent than the man.

As he went to the washing and changing rooms after exercise, already planning in his head how to dissipate the underground hero's suspicion, Bruce got the chance to look at the mirror, noticing something that may have contributed to the man's wariness.

Through the kid's braids, he could see small patches of his hair turning blue-grey, much like Bruce's own hair from back when he was alive.

Another minute of waiting for the place to empty out, Bruce got the opportunity to take off one of his contacts to reveal bright red eyes, much like the base color of his own soul and quirk when outside the void.

Looks like they finally got their answer as to what other physical changes long term possession could result in.

Now that he was thinking about it; Bruce took his shirt off, going over every scar the kid had on his arms and torso.

It took him a minute, but he found it; the small fragment of a scar Bruce himself had back when he was alive, beginning to spread through the kid's body.

If they were right, and he prayed they were right, the kid's body would return to normal as soon as he's given back his body; much like it did with En when he took over his body for more than a day.

However, there was also the risk of the scars not leaving him, of the colors not fading away.

Bruce picked up the One for All phone and sent Toshinori one message; 𝘚.𝘖.𝘚.

The kid was called in to a private meeting with the hero before the next class could even officially start.

Chapter Text

"Third, are you all right?" Toshinori asked as he settled down on the sofa in front of him; they've gone outside the school, not wanting the rat to listen in on their conversation through security cameras.

"We've gone too far" the vestige said heavily, carding his fingers through the curly hair he's unbraided in order to hide the kid's new highlights "He's got my scars, Toshinori. Or at least he's starting to get them"

The blonde man froze, a worried expression taking over him as he sat down, trying to keep his cool for the sake of the kid panicking in his mind.

He's already known that there was something wrong based off the uneasy feeling that lingered in the void from before Bruce even sent that message.
But still, he never imagined it to be that bad.

"Is he okay?" He asked "Did he get anything fatal?"

Bruce shook his head "No, nothing fatal, fortunately. But we need to give him his body back, and possibly wait a few more days before continuing this experiment, if he even wants to continue it" 𝘐𝘧 𝘠𝘰𝘪𝘤𝘩𝘪 𝘸𝘰𝘶𝘭𝘥 𝘦𝘷𝘦𝘯 𝘢𝘭𝘭𝘰𝘸 𝘪𝘵 he added in his mind, knowing how protective his spouse was over his precious nephew.

Toshinori nodded "We should find a place to put you to sleep"

They went to his apartment, willing to risk nosy employers — stalkers, in all honesty — for the kid's sake.

The return of the soul went well, but the kid's body still needed time to adjust.

They were lucky that Toshinori had formed a good relationship with Inko that allowed them to keep the kid in his apartment — with her permission — until his body returned to normal.

He had to call sick to school and eighth had to sort out so many things with both Nedzu and Inko.

Honestly, in a twisted kind of way, they were a little grateful for the health complications caused by One for All when the kid first received it — as well as Nana insisting on Toshinori meeting Inko before giving Izuku the quirk —; it allowed them to show Inko that they truly had the best interest in mind for Izuku, as they knew exactly how to care for him in ways not even the doctors knew how, and allowed them to gain favor with her without letting her in on the secret.

She saw how safe Izuku felt with the man, became one of the very few who knew All-Might's secret identity, and had his word and guarantee to keep Izuku safe.

Of course, it took a lot more than that to get her to fully trust him with her child, but she did, and both he and the other vestiges were forever grateful for that trust; for it allowed them to care for the kid in the necessary ways only they knew how without having to hide much from the person who deserved to know the most.

They may not have been able to tell her about One for All, but at least they were able to give her a peace of mind in regards to Izuku's well being and safety.

The kid ended up staying with All-Might for a week, with Inko coming to visit and even staying for several nights just to make sure that he was okay.

Yoichi — who they introduced as one of the ghosts Toshinori was capable of seeing through his quirk — was able to ease her mind and assure her that Izuku would be just fine and it was just another complication of his late quirk's development.

He relayed the information and details he saw through Toshinori, as he didn't wish to possess him during a time when he needed to utilize all the void's resources in order to monitor his nephew's condition. And he also knew whose voice of reassurance she needed to hear at the moment — other than her son's —, and it wasn't his.

Once Izuku got better, it was actually Inko who insisted he stay in bed and take it easy for at least another day or two, with Toshinori and the other vestiges being quick to agree with her out of worry.

That was the first time it ever happened — given, it was also the first time since Hikage's era that a possession lasted for so long —, and it was absolutely terrifying.

What if he died because his body began forming into a duplicate of Bruce's; who was physically a corpse at the moment?

What if he couldn't get his body back to the way it used to be because he's been apart from it for too long?

What if he started receiving chronic or phantom pains from the events of Bruce's own death?

They couldn't risk letting him leave early. Not this time. Not until they made sure that he truly was okay and with no lingering side effects beforehand.

When the kid finally came back to school, eighth monitored him as closely as he could; making sure that he actually was okay and wasn't faking it like he was prone to do after bad fights and the such.

Following Inko's wishes, the vestiges kept a very close eye on the kid, making sure that he still had his appetite and wasn't randomly writhing in pain like he did back in the apartment.

They were aware that they may have coddled him a little bit, but they couldn't really be blamed for that; they were really scared.

The sudden changes in the possession's nature, along with the still ongoing development of the kid's own quirk, meant that they couldn't take any risks, at least not until they knew that he truly was okay.

Yoichi didn't allow him to continue the experiment. Not for a while.

And it took the kid trying to convince him for several weeks before he finally agreed, under one condition; none of them were allowed to reside in his body for more than two days in a row. And even if it got to that point; they still needed to wait another day or two before going back in again.

It was fair, it was safe, and it was exactly what they needed; rules; not the unspoken ones like minimizing damage that they all knew without having to say it, but ones that kept the kid and all future successors safe from possible detrimental effects of the possession.