45

Chapter 45: Gym Time – Part IXSummary:

Quirk Analysis of:

Shihai Kuroiro - [Black]

Kosei Tsuburaba - [Solid Air]

Neito Monoma - [Copy]

Notes:

(See the end of the chapter for notes.)

Chapter Text

"How in the world did you manage to book a gym and find a teacher available to watch over us with so little forewarning?" Neito asked, looking surprised and interested by the unusual—but recurring—exploit. "I've looked at the reservation schedule before and I couldn't find an open slot for the life of me. They were all either already taken by our seniors or missing the teacher surveillance necessary for Quirk testing." 

Izuku chuckled at the blonde's question as their group stepped inside the building. Neito was probably exaggerating, but it was a valid point. 

"It wasn't easy, I tell you. I've spent ages looking for free slots without success. This month is even worse than usual, since the exams are coming and everybody's rushing to do some last-minute improvements." 

"Yes, I figured that would be the reason for that mess," Neito agreed. "So, what's your secret?" 

"It's something obvious and far-fetched at the same time." He rubbed the back of his head. "I noticed that the names missing from the lists of available teachers from each slot followed a sequence. For example, Cementoss always has Wednesdays and Saturday afternoons off," he said, as the Literature Professor was the one they were waiting for. 

"But wouldn't that mean that he shouldn't be available now?" Setsuna, walking beside the blonde, asked. 

"Yeah, it would. That's why he's not on the reservation list for those two days," Izuku nodded and grinned. "But here's the loophole. 'Off the clock' doesn't mean 'completely unavailable.' Most of our teachers really do love their work and, if you ask nicely enough, they might just come to keep an eye on us even when they're supposed to be taking time off work." 

Neito let out a laugh as he shook his head. "My, it really is painfully obvious." 

"That's some dedication," Kosei noted with a disbelieving huff. "I'd much rather relax." 

"I hope that your 'asking nicely' didn't require you to grovel," Setsuna snickered. 

"Nah," he shook his head, "I just had to get him a box of manju. Miss Midnight told me they're his favorite, and she was right on point. He loves them, and he gladly granted to my selfish request." 

"Bribery, I see," Shihai, who had been silent for their whole walk, whispered. "I did not expect you to resort to such methods, Midoriya." 

"I'm very serious about training, and it was just a small gift. I can't let something like boring norms keep us from improving, can I?" He winked, making the black-skinned teen sneer. 

"Ah! Fucking right," Togaru sneered, his neck tilted back as he chuckled. 

"I can agree on that," Sen, hands in his pockets, huffed. "Better here than wasting a whole afternoon doing nothing." 

"You're certainly full of surprises," Neito concurred before seeing and welcoming the approaching professor. 

Once the whole group was inside and properly divided between those that wanted to train by themselves and those that were just there to watch, Izuku began his work with the last three members of 1-B. 

"So, who would like to begin? Monoma?" 

"Oh, I'd rather go last," the blonde said, raising a hand to refuse the offer. "I've been told that watching your analysis is rather interesting, so I'll gladly wait." 

"Uh, you sure? I thought you'd want to go first for sure," Kosei said, looking a bit lost. 

"Don't go getting cold feet now, Copycat," Togaru grumbled, crossing his arms. 

"Trust me, I'd love to start, but you know that I prefer to study my part beforehand," Neito pointed out, meeting the other's challenging gaze. 

"Fair enough," Izuku shrugged, knowing that nothing would convince the imitator to step forward first. "Kuroiro? Tsuburaba?" 

"I shall try," the white-haired teen smiled, stepping forward while keeping his hands behind his back. 

"Perfect!" Izuku smiled, happy to finally get working on [Black]. Shihai would have probably come to him sooner if it wasn't for his friendship with the previously reluctant Neito and the shyness that made him keep a certain distance between himself and Kinoko at all times. 

"Let's start by going over what you already know about your Quirk. I know you can meld into shadows, but I don't think that's just it, as I've seen you enter dark objects even when they were under direct sunlight." 

"And you would be right," Shihai smirked. "[Black] grants me the ability to discard the limits of my mortal shell and meld into anything that is touched by darkness, be it naturally or through external circumstances." Then, without any need to be asked, he disappeared, letting his empty clothes fall over his shoes. "And, as you have noticed, even a white pavement can become mine once a shadow is cast over it," he said as he reappeared as a pair of eyes and a smiling mouth on the floor. 

"And it's a Transformation Type," Neito added, providing another piece of information. "With some vestigial mutations, of course." 

"Of course. Thank you both," Izuku nodded before looking to the smirking teen. "The spot where you're fused to the object is slightly darker than the rest, as if you were an additional shadow over it..." 

"It's always like that," Setsuna commented. "But it's not like he's easy to see when everything else is already dark." 

"And he can't be hit while he's inside that anyway," Kosei shrugged. 

"True, but it is a weak point to remember," he added. Underestimating even the smallest weakness could get people killed. It had already. "If I noticed him and managed to shine a light to get him out, I would already know where to strike." 

"Kuroiro, didn't you get caught yesterday for that precise reason?" Neito asked rhetorically, seeing the point of the warning. "There are at least eight students in our year that can easily create lights on a whim. One fifth of us. You can't take the risk lightly if you don't want to repeat the experience." 

The hidden teen snorted but agreed. "I will keep that in mind." 

"Good." Izuku moved, walking around the dark spot to examine its surface. "You don't seem to be limited by mass or size right now..." 

"Because I am not," Shihai huffed. "The size of the objects I occupy does not trouble me in the least. I might become as small as a button if I wished to." 

"But you haven't become as big as the entire floor right now," the greenette pointed out. 

"Indeed, but that is a choice I have made voluntarily. Watch." 

The dark spot started to rapidly stretch, turning a small spot on a single tile into a wide puddle. It was certainly larger, but a far cry from the whole gym floor. The eyes and mouth had also kept their original size. 

"So you can occupy a larger space..." Izuku contemplated. "But does it offer you any advantages? All I see is a bigger target." 

"I may come out and return to my real body from any spot I occupy," Shihai said, letting a hand emerge from one side of the stain before retracting it and repeating the action meters away. 

Izuku hummed while pointing at the spots the other had just used. "Can you do that simultaneously?" 

"I can, but it requires a great deal of effort and focus, which are more often than not required to keep myself moving or hidden," the other grumbled. 

"So that's something that will need training," Izuku noted. "Well then, come back up. It's time to experiment." 

Shihai obliged, slithering back to his clothes. "What would you have me do?" 

"We'll start by discovering the limits of what 'black' means for your Quirk," Izuku said as he went for his bag, taking out a thick folder full of colored paper. He started orderly laying out the sheets on the ground under the curious gazes of the observers. 

"What's all this?" Kosei asked curiously. 

"Color samples. We start from absolute black," he pointed at the rightmost sheet, "and we move on to lighter ones until we get to something Kuroiro can't meld into." 

"Shouldn't be hard to figure out," Sen commented as he looked towards the right, since more than a few pigments could seem too far from black to work. 

"I wouldn't bet on it," Izuku shook his head. "I prepared these to see at which point something turns from what you can consider a 'dark object' to a 'light object.' I'll be using color models to pinpoint Kuroiro's range." 

"You mean, like, what was it... That red, green, and blue stuff to mix colors?" Setsuna asked. 

"Not only that one, but yeah, that's pretty much it," he nodded before setting down the last sheet and turning to the group. "Can somebody open the door, please? We need natural light on these so that shadows won't contaminate the experiment."

"Sure," Sen and Togaru moved, letting in more sunlight. 

"Alright," Izuku said, opening a notebook and pointing with his pencil. "I can explain as we go, so let's start with the pure black." 

The analyzed student nodded, disappearing inside the darker sheet offered. 

"Perfect. You can move on to the next one, I'll just keep track as I talk," he said, making Shihai switch from paper to paper as he checked each one. 

"The first one is what we register as the darkest possible color: black. We perceive it as the total absence of light that stimulates any of the three types of color sensitive cone cells in the human eye and with the lowest brightness when compared to its surroundings. Going by two of the most used color models we use nowadays, sRGB and HSV, black is always on the lowest point of the scale. For the standard Red Green Blue color space, it's at (0, 0, 0). White is on the opposite side with three 255s, the upper limit. For the Hue, Saturation, and Value model, we find black at (0°, 0%, 0%) and white at (0°, 0%, 100%), since the value of the Brightness, or Lightness, is what keeps the two apart and the one we should focus on." 

"And those you placed near it are shades of black, right?" Neito asked as he looked at several blackish sheets Shihai was moving in. 

Izuku smiled at Neito's knowledge, gained in hours spent of looking for the perfect shade for his own Hero costume. "Precisely." 

"Wait, isn't that, like, dark brown? And that one is blue," Kosei pointed out. 

"Black Bean and Cool Black," he answered. "They're still relatively close to black. Dim Gray is the one further from it and it's still only a (105, 105, 105) and 41%. Not even close to the true middle point." 

"Which should be this one, right?" Shihai asked, having reached the end of the first part of the greenette's trial. His head was out of the paper, and he was examining the next sheet with disappointment. 

He showed a wide, satisfied smile. "Yeah. You're currently on what I hoped could be your limit: (127, 127, 127) and 50%. Practically the middle ground between black and white." 

"I see. I don't feel like I can go further," the white-haired teen admitted. 

"Perfectly understandable," he nodded. "Now we know that [Black] considers 'dark' every color that is even slightly on black's half on the graph, which means that you could try a lot of stuff even under the sunlight. You may be able to increase that limit with training, but I think it would be unlikely without a fundamental change in how your Quirk functions." 

Shihai smirked. "No matter, I shall strive with what I'm given. If I am to be one with the dark, so be it." 

"Good attitude," he chuckled. 

"Be careful or you'll be cutting yourself on all that edge," Togaru snorted. 

 "Look who's talking," Setsuna rolled her eyes with a smirk, making the teased reply with a bladed middle finger. 

"What's next?" Shihai asked. 

"Something that's been on my mind since I've first seen you use your Quirk," Izuku responded, going for his bag again as he talked. "I want to know if you can move with the object you're melded into." 

"Why wouldn't he? He can just stay put as somebody moves the thing he's in," Kosei said, missing the point. 

"That's not what he's wondering," Neito grinned, bringing a hand to his chin to contemplate the idea. "Move with the object, as in 'actively moving said object around'? Interesting thought. How do you support your theory?" 

"Nothing concrete for now, just a hunch," he answered truthfully. "But the fact that Kuroiro hasn't yet doesn't mean that he can't. For one, I've never seen him fuse with anything that could move, only furniture, floors, and walls. But if I give you something like this," he threw a black ball over to the group, "maybe things will change." 

Shihai snorted and disappeared inside the sphere, his eyes appearing over the surface. 

"Try to get a feel of the space around you. You can slither around when you're a shadow yourself, so try to stretch that shadow to cover the whole ball. Then, try and will yourself to move." 

The group observed the unmoving item for a few minutes. The silence—occasionally interrupted by the teens' grumbles—was finally shattered when the ball started rolling away from its spot. 

"Damn!" Kosei shouted, pointing at it as it picked up a bit of speed and drew some circles on the ground. 

"Look at him go!" Setsuna exclaimed while Neito lightly clapped. 

It didn't take long for Shihai to come out, wobbly and almost falling on his ass before being caught by Sen. 

"That... was... weird..." he muttered, a bit nauseated. 

"I never said that it would be easy, but I'm sorry if that was too much," Izuku sheepishly excused himself. 

"No... It's fine. Perhaps I shall try with something that won't roll, next time." 

"I believe that we could find a myriad of things that can move without that trait," Neito nodded. "We may have to pay a visit to the Support Department." 

"Dude, imagine moving around in a black suit of armor," Kosei laughed. 

Togaru let out a riveted hum. "It would be perfect for training," he said with a smirk. 

"There are a few options I can think of..." Izuku agreed, even if he knew that finding the perfect one would have typically been way harder than a simple tour in Mei's lab. 

Shihai was the type to prefer stealth over assault and brain over brawn, so he wouldn't find a heavy armor to his liking. Smaller things couldn't be used for fighting better, and he could already hide perfectly in most cases. He wasn't the "Scheming Hero" for nothing. No, what Vantablack needed wasn't an armor, but a weapon, something that made him harder to catch or kill, but that could be used for the same purpose on Villains. 

"... But this, I think, could be one of the best," he said, opening a small container before the group. 

"Is that... oil?" Kosei asked, confused. 

"It doesn't smell like it," Togaru pointed out. 

"It's just water dyed black," Izuku shook his head. "Nothing special by itself, but Kuroiro could turn it into something incredible." He turned toward the teen in question. "This could be the perfect way to improve your Quirk use. It will probably be incredibly hard, since I doubt that a liquid will be as easy to control as a solid, but if you can manage to keep this or any other fluid compact enough to move around in, it'll be the best weapon you could ask for." 

"But wouldn't he, ya know, drown?" Setsuna asked, raising an eyebrow. 

Izuku smirked and asked, "Kuroiro, do you need to breathe when you're melded?" 

The student in question shook his head. "My transmuted form has no need for it, as I do not retain any real part of myself besides my eyes and mouth as long as I'm inside a shadow." 

"There's your answer," he winked at the lizard girl, who sneered in response. 

"Not bad. Not bad at all," Neito mused, showing a thoughtful look. "He would be virtually untouchable, since the liquid could be moved to evade hits or just take them without relaying the damage on him. He could restrain and, if required, suffocate Villains until their collapse." 

"He could also drastically reduce an enemy's visibility and cause further damages with some electricity or ice. And, if he manages to stretch even further, he could move a weight of thousands of liters," Izuku added. "A lot of advantages for a theoretically low risk." 

"Though he'll have to train hard to reach that point," Sen commented. 

"Not a problem," the white-haired teen interjected, taking the container for himself. "As if I'd let myself be held back from tapping into my true potential by a cup of dirty water." 

Setsuna snorted. "Alright, Edgelord, just don't get lost in that glass." 

Shihai huffed at her and bowed lightly to Izuku, expressing his thanks to the "Shadow Master." 

- Goddammit Tokoyami, I swear to god... - he rolled his eyes as [Dark Shadow], somewhere else in the gym, cackled madly.

"Come on, Tsuburaba, your turn," Togaru told to the brunette, making him step forward. 

"Yeah, yeah, I know," he huffed, looking a bit uneasy. 

Izuku knew that Kosei had suffered of a slight self-confidence problem during his first few months in high school. [Solid Air] was a nifty Quirk, but it lacked the power to withstand most of his classmates' attacks, let alone the power of their Quirks. His air shield had been broken by Bakugo through simple raw strength during the cavalry battle, and he still blamed himself for his lack of power that had cost Monoma's team their points. It had taken Vlad King's teaching to have him leave that dejection behind. Izuku would be fast forwarding that process too. 

"Alright, Tsuburaba, can you tell me about your Quirk?" Izuku asked with a welcoming tone. 

"Sure," the other looked up, blowing to create an air wall and show the power in action. "It's called [Solid Air], and it lets me make this kind of things. I call them platforms or walls. They're just what the name says: solidified air." 

"Alright." Izuku brought a hand to his chin as he moved to inspect the floating shield. "How long do they last?" 

"A few minutes or until they're broken," Kosei answered, tapping on the wall as if it was glass. 

"Better take a precise measurement for that," he said, taking out a stopwatch and asking to produce a second one. "And do you know how much strength is needed to break them?" 

"Not that much," the teen huffed. "A good punch can break through." 

"Then we'd better get something more precise for that too later, so that we can see how you'll improve with training," he offered. "Feeling that you're improving is nice, but seeing your progress as a series of rising values always makes me feel better. It's also easier to understand that way." 

Kosei looked surprised for a moment before shrugging and nodding. "Yeah, sure." 

"What else..." Izuku muttered, faking a thoughtful look. "How big can you make these? Does the size depend on your lung capacity?" 

The brunette looked surprised again. "Yeah, depends on my lungs. I can make small stuff with a single puff," he showed an air shield that was as big as a fist, "but the ones I've just made took me a big breath." 

"Oh, so you can control and limit your output! That's great!" Izuku rejoiced. "Since your Quirk is breath dependent, I'd suggest for you to join Fukidashi in his singing lessons." 

"Singing?" Kosei asked, checking if he'd heard right. "Why?" 

"Breath control, oxygen efficiency, precision in inhalation and exhalation, mastery of minute movements," Izuku stated, knowing that the other needed some convincing. "You could also improve by swimming, but you might not be able to go through everything you'd need every day after Hero lessons, and it wouldn't work for the precision you desperately need. Singing requires you to turn you whole body into an instrument—lungs, stomach, throat, and back—and splitting your focus that way will make you better at multitasking. So, singing is your best bet." 

"Ugh, fine..." the boy sighed. "I'll do it. Just keep cameras away." 

"You betcha," Setsuna grinned, crossing her fingers behind her back. 

"I wouldn't make fun of you for trying to improve yourself," he said, hoping to partially defuse future conflicts, before stepping over to the air constructs. He tapped the smaller wall and grabbed it, sizing it up and comparing it to the other one. "It's not only smaller, but thinner as well..." he analyzed. "Do you have any control on that part, or does it only depend directly on the overall size?" 

"Uh... dunno, I've never directly tried to make things thinner before," Kosei answered, a tad confused. 

"Come on, you haven't even tried to make them thicker, Airhead?" Togaru grumbled. 

"Hey, cut me some slack! It's not like I had a ton of people to train with before U.A.!" 

"Yeah, Pincers, it's not like you tried to take those blades off your arm by yourself," Setsuna grinned, scoring a second middle finger. 

"Want to try?" Izuku proposed. Kosei nodded, inhaling deeply to give it his best shot. "Try not to focus on the size. Maybe... push it forward, not around." 

Setsuna, as the she-devil she was, couldn't help but suffocate a snort at the unintentional innuendo. To his defense, Izuku could say that he wasn't completely at fault. Kosei had never given him very precise instructions on how he managed the feat, so he had to adapt to using the guy's own words. 

The teen needed more than a few tries before the air walls started to develop any changes in thickness. After a long ten minutes of exhaling breathing in and out, the last products were noticeably better than the first ones. 

"Yep, that's better," Sen commented, trying his fists on the better versions and seeing that they weren't breaking apart as easily as they usually did. 

Another was shattered to piece by Togaru's blades. "... But not perfect." 

"It's already a remarkable growth though," Neito chuckled. "Good job." 

"Uh, thanks." Kosei rubbed the back of his head, still a bit out of breath. 

"Well, it seems that the walls at maximum output can hold for five minutes and thirteen seconds, give or take a few," Izuku said as he put away his stopwatch. "Now, I've got two more ideas I'd like you to try. First, how fast can you make the smaller version you showed earlier?" 

"These small things?" The teen puffed a couple into existence in just as many short exhalations. "Just like that." 

"Perfect," Izuku smiled. "And do you have a maximum range for your breaths? I've seen you mostly use them in front of you, but can you send them further?" 

"Ah, yeah, that's easy. I think I can do about..." Kosei did his best to send an air wall as far from himself as possible, letting Izuku measure the distance. 

"Six meters... should be enough for mid-ranged attacks." 

"'Mid-ranged'?" Setsuna piped up. "How'd that work?" 

"I can think of two ways," Izuku said, lifting that many fingers. "One: If you put an obstacle in front of someone who is running or flying, they're almost bound to collide with it. If that obstacle is virtually unmovable, they may hurt themselves on it, badly. Add to that the surprise of hitting something partially invisible with your face or having it appear between your legs... the applications are many." 

Izuku chuckled as Kosei's eyes widened as his brain took in the information. 

"Two: He just proved that he can make the walls thicker, so the same must be possible for the opposite. There shouldn't be a minimum thickness required to keep the walls together, since it's solidified air, and that would let you create disks with razor sharp edges. Imagine running directly against one of Kamakiri's blades." 

The whole group but the insect teen, who smirked madly, frowned at the image. 

"I don't know if Tsuburaba will have to keep making flat and round surfaces, but—seeing what he has accomplished today—I think that modifying the shape isn't so farfetched. So they could, theoretically, count as ranged attacks." 

"But, since he can't throw them, there would be no force behind them," Neito noted. 

"True, they would only work on moving enemies or as deterrents to keep them from moving. Unless he gets a way to do just that, of course," Izuku smiled, knowing full well where the guy's specific training could go. 

"Damn, that seems cool as hell," Kosei grinned, finally completely engrossed by his prospects of growth. "What was your second idea?" 

"The fact that you're mostly using your shields to block, and never to deflect," Izuku pointed out, taking out his notebook to show a drawn example. "See, if you tried to stack a few walls, one over the other, you would get a better shield, but it would still fail against great bursts of power." 

"Yeah. I don't think I could stop one of your punches even with ten of those," the brunette shrugged. Izuku could break out of Ibara's vines and Shoto's ice, and both of those outclasses [Solid Air] in offensive and defensive properties. 

"Because, again, you're thinking of stopping the blow. But that's not what you really want!" Izuku said before rushing forward and punching the air and stopping just a span away from the guy's chest. He then repeated the action closer to his head, making his hair move from the wind. "There. The first was to show something that can be counted as 'stopped,' while the second was something 'deflected.' Did either hit you?" 

"N-No?" Kosei replied, momentarily stupefied. 

"Right. So, if your goal is not being hit, there is fundamentally no difference between the two. What is different, though, is that deflecting is way easier than stopping. You can ask Kendo, or Rin, or Ojiro, they would all give you the same answer." 

"So, instead of simply stacking walls over each other... You could bend them toward a particular direction to have the blow 'slide' to the side," Neito offered, getting to the point before Izuku. 

"Precisely," the greenette nodded. "Blows might just slide past, and that would usually mean an opening for you. With enough disks you could even divert something as big as one of Todoroki's bursts." 

Clear examples like that were the best to get the guy's interest. 

"For real?!" Kosei exclaimed, dumbstruck. "Damn! I so gotta try this!" 

"You've got time," Izuku chuckled. "Though I think that Todoroki wouldn't disdain another training partner." 

The group looked over at Shoto, who was sliding around on his ice to keep up with Mina while blasting fireballs against Tetsutetsu, who took them while yelling for more. 

"... Maybe later," Kosei mumbled, generating an understanding laugh from the others before stepping back to let the last of the trio take his turn.

"Well, it seems that we have finally reached my turn," the blonde noted, rubbing his hands together in anticipation. 

"Yeah, come on." Izuku gestured for him to take the stage. 

Neito Monoma, Izuku's third to last case... and probably the hardest. 

"I'm going to be blunt from the start, Monoma," Izuku admitted. "[Copy] is uncanny. On a surface level it seems to be incredibly simple, but it might just as well be one of the most phenomenal and interesting I've ever seen, and surely one of the hardest to work with." 

"You're one of the firsts to say anything about it being phenomenal, but only the last to say that it could be too difficult to use," Neito chuckled. "But hardship is part of the job, isn't it?" 

"It is, but I didn't mean it like an insult," he assured. "I have thought of several possible applications and alterations for your Quirk, but I doubt that you haven't already tried most of them before." 

The blonde simply shrugged. "You flatter me, but I'd rather hear them all before throwing in the towel." 

"Of course, give me a second..." he said, taking the notebook that was proof of how much he had tried to analyze Neito's power. It helped for putting on a show. 

Izuku faced the cunning blonde, starting a quick paced exchange of information. 

"Quirk name: [Copy]. You can use almost any Quirk after coming into contact with its respective user. Do you need to touch skin, or you're fine with hair, horns, or nails?" 

Neito hummed, pensive. "Skin is surely the simplest way, but not the only one, no. Hair and horns work, but I have never tried using nails as the point of contact." 

Izuku replied by extending his arm and showing his index finger to the guy, who raised an eyebrow before smirking and touching the fingertip. 

"Ah, it seems to work just fine," Neito replied after a momentary, quiet, and almost imperceptible flinch. 

"Alright," Izuku nodded. "In that case, am I right to assume that anything could work as long as it's connected to a person?" 

"It's very likely," the blonde smirked. "Even Shiozaki's vines and Fukidashi's speech bubble work just like everything else so I'd say that we could take it as granted until proven otherwise." 

- And I've not seen it disproven yet, so you're fine on that front. - 

"Can you activate [Copy] on discarded parts like hair or blood?" he asked, continuing the act. 

Neito's shoulders dropped a bit as he sighed. "Sadly, I seem to be limited in that regard. [Copy] does not recognize a Quirk from anything that's been cut off from the original source. It feels as if I'm touching a withered flower: it was part a living being once, but whatever life it held is long gone." 

Izuku smiled lightly at the other's dramatical exposition. "So, for example, you could copy Tokage's Quirk even from one of her detached arms, since they're still connected to her body-" 

"Yup!" Setsuna interjected. 

"-but not Kamakiri's from his blades once they've left him." 

"Precisely," Neito nodded. 

"Copycat can't use my Quirk for shit anyway. Won't work for some bullshit reason," Togaru commented, his tone biting. 

"As I've told you since you revealed Midoriya's discovery, I simply lack the organ to produce your silk, Kamakiri," the other replied, imperturbable. "As much as I would like to, I can't imitate vestigial mutations." 

"Still bullshit," the taller teen rolled his eyes. 

"Anyway, that cuts off any possibility of letting you store hair or blood samples on your costume to keep Quirks at hand," Izuku interjected with a dejected hum, tracing a line over said theory of the notebook. 

"As much as I would have enjoyed holding a vast assortment of powers, the prospect of not having to keep furballs, nail clippings, and blood sacks on me at all times makes the loss somehow more bearable," Neito joked as he shook his head. 

Kosei stuck his tongue out, seemingly disgusted. "Gross." 

Setsuna rolled her eyes but kept her silence. 

"We may try alternative forms, like turning one of Pony's horns into a ring or something similar," he proposed, "but I fear that it would become useless as soon as the connection between the object and her is severed." 

Neito nodded. "It's highly likely. Her horns may be just a bit more 'alive' than Kamakiri's blades, but they're both Quirk products. She can't hold the connection forever." 

"True," Izuku said as he crossed one more line. "Moving on. After a touch you gain full access of the Quirk, but do you also receive information on how it works?" 

"Yes, I do receive some basic information on the Quirk's functioning, but I don't need to actively copy the Quirk to activate the scanning process." 

"You can examine any Quirk before taking it?" 

"Yes," the blonde concurred, "though the process takes a few moments and may not be optimal for the rush of combat encounters. I think of it as a rough safety measure to avoid powers that may hurt me." 

Izuku hummed sympathetically. "Right, so I guess you don't get a full explanation of what's a vestigial component and what's an intrinsic property of the Quirk?" 

"It's not like reading a book with a neat explanation, no. It's more like a 'feeling' and my own extrapolation," Neito admitted before turning to the rest of the group. "For example, I know that Tokage's teeth and Fukidashi's head are vestigial mutations, but only because those aren't relevant to their Quirks' functioning. When I use [Comic] I don't get the same throat reinforcement that Fukidashi has, so I can't handle more than one of his shouts before destroying my voice. On the other hand, I also couldn't feel Kamakiri's secret organ—even if it's vital to his Quirk's functioning—because it is another vestigial mutation, which I can't copy," the teen shrugged and smiled while raising his hands in a "can't do anything about it, so why bother?" pose. 

Kamakiri grumbled again but didn't interject. 

"When it comes to parts that are fundamental to a Quirk, [Copy] can reproduce them without error, even in the case of Mutation Types." 

"How do Mutations work for you?" he asked, taking notes he didn't need. 

"I don't get the experience that comes with living with additional or different appendages, so that's always a tad weird for me, but I make do," Neito chuckled. "The only two examples I can give you right now are [Vines] and [Horn Cannon]. Pony's Quirk gives me a pair of horns-" 

"Black devil horns," Shihai pointed out with a smirk. 

"Classy, ringed, black devil horns, if you please," the blonde replied with the same grin, moving his hair in the spots the two appendages had appeared before moving back to his retelling. "I can use them as intended, growing them back instantly after shooting, just as Pony does. When the timer's over, they simply fall off." 

"When did you try Shiozaki's though?" Kosei asked. "Can't remember that at all." 

"I copied [Vine], but never activated it," Neito admitted. "I understood that doing so would permanently change my hair to look like Shiozaki's, but my control over them would fade as soon as the Quirk left me... together with the safe way to hold plant cells meshed with my own. I do not know if the vines would fall on their own but cutting them off at the scalp would have been a risky procedure, so I didn't take the chance." 

"Uh, makes sense," the brunette rubbed his head, as if imagining the weird feeling the event would bring. 

"I could have cut them all off with my eyes closed," Togaru pointed out. 

"Then I'll keep that in mind if I ever want to risk it." 

"Just admit that you didn't wanna lose your own hair," Setsuna smirked. 

"Do you think so little of me? I'm hurt!" Neito replied dramatically, but soon winked back. 

"It may be a good thing to try at least once," Izuku said. Neito's fears were founded, but the problem could be easily avoided by keeping a copy of [Vines] until the plant-like hair was removed, or by using a high-speed regenerator like [Lizard Tail Splitter]. Of course, that would imply surpassing living through the headache that Setsuna's Quirk produced. "Getting familiar with every Quirk in our classes would only work in your favor." 

"Um, it surely would," the blonde mused. "Alright, I'll try it later, perhaps when we can have Recovery Girl close at hand." 

"Better safe than sorry," Izuku agreed. "Next... You can copy a total of three Quirks at the same time for around five minutes each, right?" 

"Yes, although my time limit has been slowly rising since my childhood, so I imagine that I could increase that further, especially now that I'm surrounded by Quirks I can copy without repercussions." 

"Ah, that's good to know. The increase happened as you got more comfortable with new Quirks?" 

"Something like that," Neito replied, pensive. "[Copy] feels somewhat like a mold for me to fill with the power of others. The framework is always mine, but it stretches ever so slightly each time I have it adapt to something else." 

"A good mental image, thanks..." Izuku hummed in understanding, writing a few things in his notebook and crossing off others. If one were to look at it now, they would recognize a good pattern of ideas that had ended up on something "simple." 

"Alright, I think that I've got your training method," he declared as he took his nose out of the pages. 

"Hit me," Neito smiled, opening his arms. 

"First, you will need a lot of Quirkless training," he started, immediately noticing a few raised eyebrows. "[Copy] is great, but there is a chance that you may end up by yourself during Hero work, probably after being either separated from others or caught in a fight for too long. In those cases, you would be effectively Quirkless, and your current self is lacking." 

"I feared a harsh judgment, but I find myself agreeing with you," Neito sighed. 

"It's not the end of the world," Kosei tried to be supportive. 

"Far from it," Izuku concurred. "Everyone here should learn how to fight Quirkless. You never know what situations you may end up in, and something Quirks are just too risky to use." 

"How'd mine be risky? I know how to keep my blades in check," Kamakiri commented, doubtful. 

"A narrow corridor filled with explosive gas. One wrong move, and your blades could create the spark necessary for ignition," Izuku explained, trying to be concise and blunt as needed. 

"... Right," The insectoid teen grunted and crossed his arms, apparently comprehending his point. 

"Your body type is also close to Shinso's so you would be good sparring partners too. Just a word of warning: I drilled him to hell and back before the Sports Festival, so don't underestimate him." 

"I'd never do that," Neito responded, shaking his head lightly. "He had Bakugo on his ass and walked off with one of the best dramatic exits I've seen. I respect that much dedication to the role." 

"Alright, I'll give you some pointers later," he chuckled. "When it comes to [Copy], instead, you should probably train yourself by copying as many quirks as you can in as little time as possible. Running around the gym to continuously switch between them after short activations could break that mold of yours and expand it faster than ever. I think that this way could also let you increase your holding limit from three to four or more." 

"Ah, that would certainly be an interesting development..." the blonde mused, content with the prospect. "Is there anything else you want to know about?" 

"Yeah, there's one thing I need to ask: When you discard a Quirk, are the effects you caused through it canceled?" 

"It depends," the other replied with a sigh. "I can't keep things altered with [Size], but anything I use [Weld] on will remain stuck." 

Izuku hummed again. "Then it might be determined by the way their Quirks work, not by yours... [Size] keeps the alteration active with an indefinite time limit, so cutting off the source makes everything return to its original status, just as when Kodai switches it off voluntarily. Instead, [Weld] is only activated momentarily, even though the joined objects can remain so for hours." He wrote a few more phrases on his notebook, looking pensively at the result. 

"Did you think about something weird and new?" Setsuna asked, interested. 

"Yeah, but we have no ways of proving it right now anyway," he confessed with a huff. 

"Come on, don't leave us hanging," Kosei said, being too curious to accept only a hint. "What is it?" 

"I think that Monoma could ignore time limits of other Quirks by deleting them and copying them again," Izuku said. 

Which had been quite the accidental discovery, but one that could serve him well. 

The blonde's eyes shined with interest at that. "Oh? What's your theory?" 

"I think that [Copy]'s way of imitating powers could be able of resetting itself after each switch," he stated. "And that would mean ignoring certain limitations, especially those that are time dependent." 

"Wait, how would that work?" Sen asked with a dubious tone. 

"Since [Copy] always returns to its initial state after it stops imitating another Quirk, it should be losing any 'conditions' set by said Quirk, time limits included. Which would mean that, once Monoma takes the same Quirk again, he should be free from any previous constraints," he explained. "Oh, any Quirk working like a charger with limited shots would probably fall under that rule too. Anything that doesn't consume your own body's resources or cause damage would be improved by [Copy], I think." 

"Oooh... That's very, very interesting." Monoma pondered over the idea before sighing. "But you're right. We can't prove that yet." 

"Why not?" Kosei asked. 

"Nobody here as that kind of Quirk. I don't think there's one in the whole of U.A. even, or at least none that I've heard of," Izuku stated, looking at the rest of the gym. "They're kind of rare. Usually that kind of limit is a counterweight to something very strong or hard to use." 

"Uh, are there any famous ones?" Setsuna hummed, curious as to how he knew about it at all. 

"Hawks is the first I can think of," Neito smirked, going for the grandest name on the list. "[Fierce Wings] should be a Mutation Type. His feathers can move incredibly fast, but they're still feathers, so they can be burned or broken. I could simply regrow the whole thing instantly." 

That got a few impressed whistles from the group. 

"Damn, that could be cool as hell," Kosei commented with an approving grin. 

"Anybody else we may know of?" Togaru questioned, hoping for something great to fight against. 

"All Might's former sidekick, Sir Nighteye," he offered. "It's not certain since his Quirk's status isn't public, but it's very likely that [Foresight] has a time limit. Once per day or something is my bet." 

"Ah, I remember now, a power to look into the future... Such a boon without its intrinsic limitations would be terribly effective..." Shihai commented, his smirk turning evilly appreciative. 

"But imagine what good it could do!" Neito rejoiced with a clear laugh, dreamily picturing a future where he could use something like that for his work. The blonde recomposed himself, taking a breath, before turning back to Izuku. "Really, Midoriya, I have to say that I'm impressed. I don't think that I would have thought of that on my own, and the chance of stumbling upon that discovery would have been infinitesimal..." 

- You don't know the half of it, - he thought, mentally sighing. 

"It's all good, Monoma. I'm just happy to help," Izuku responded. 

"Well said!" the blonde exclaimed, clapping his hands. "Now, let's join the others! I can't wait to have our seniors eat our dust as we claim our spot at the top of U.A.!" 

"Oh god, he's changed target," Sen groaned. 

"At least we can live in peace now?" Setsuna offered, trying to see the positive side. 

"He's more likely to bring two whole years of Hero students on our asses," Togaru grunted. "Move it, we'd better be training if that's the case." 

"Sure, sure," Izuku chuckled. 

Weird how they weren't even that far off.

Notes:

Come on, it's just 3 characters, how long do you think this can get?

Trust me, I didn't think it would take 7k words, but I'm happy it did.

I really like the approach Kuroiro takes to Heroism, and [Black] is perfect for it.

[Solid Air] got a decent buff in the joint training and i liked the "prison" move, but it clearly lacked more thought.

[Copy] should have gotten more chances to shine (and thankfully it did in the last few chatpers of the manga), but Monoma's original version isn't much liked by the public and Horikoshi mostly ruined him as with Mineta. Damn gags. (Hey, psst, you want a better Monoma? Go check out FalseSeraph's "Torchbearer"!)

And that's 1-B all done!

Don't worry, training will still be a thing, just not with this style of chapters. Probably.

Up next, weird thoughts and somebody who can't sleep!

I love interacting in the comments, so feel free to leave one and speculate.

Leave a kudo or a comment if you'd like!

Thank you for reading! 'till next time!