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The first time Deku saw a red string, he thought it was a mistake.
Kaminari and Jirou had just been on a joint mission. They walked into class together. A glowing string stretched between their fingers. The farther they walked from each other, the more the string grew. From the way that it glowed, it looked like the after effects of someone’s quirk–some unknown technique a villain had used to join them together.
Deku leaned forward in his seat, to whisper to Kaminari. “What happened? Are you okay?”
“Yeah. All good. Why?”
Deku paused. He looked down. “Is that okay? With the string?”
“What string?” Kaminari asked, genuinely oblivious. He didn’t know. Jirou was the same. No matter how clearly Deku saw the thread between them, neither one of them felt it.
It took half an hour for Deku to stop seeing the line. He rubbed his eyes, and told himself he must have been tired that day. He wasn’t.
It took three days for Deku to see the next one. During quirk training, the second Kirishima used his quirk, a thin, red thread stretched between him and Ashido.
Again, Deku tried to point to it. Again, he got the same reply. No matter how clear the lines looked to Deku, no one else could see the strings.
By the time he saw one between Mirio and Tamaki, Deku understood. The red strand was a bond between quirks, an echo of energy. “Like, an ember.”
“What’s that?” Kirishima asked. “You’re mumbling, man. I couldn’t hear.”
“Oh! Sorry!” Deku dropped his hand from his chin. He waved in front of himself, instead. “It’s nothing—!”
It wasn’t nothing. What it was, Deku wasn’t sure.
The longer it went on, the more he started to understand. There were rules.
The string on someone’s finger only appeared after a quirk had been deliberately activated. The time it stayed visible varied. The more intensely the quirk was used, the longer the string was visible. Most of the strings had an end point, which was another person’s pinkie. It didn’t matter how far away the other side was. If the person was in another room, or city, or country, the bond kept going. A quirk had only one partner, and the bond didn’t change. No one else could see them.
There was a slight but growing chance that Deku could have gone insane. He didn’t think so. It made too much sense to be madness. This was something else.
“So, you’re saying, there’s something left of One for All. An echo of an existing technique,” Toshinori concluded.
They sat together in the teacher’s lounge, like old times. If Deku hadn’t been asked to be here by Toshinori directly, he wouldn’t have had permission. That way, his classmates couldn’t overhear.
As much as Deku understood what Toshinori was saying, he couldn’t bring himself to agree. He curled his hand under his chin and focused. “I don’t think it’s like that. At least, not exactly. Aside from passing it on, the quirks in One for All all had uses in combat. I don’t see how this has a use in that context.”
Toshinori tried to think, too. He looked down, considering. “If it’s not One for All, then… It’s possible you weren’t quirkless in the first place. Your quirk had to meet conditions to emerge. It’s not necessarily an echo.” His brow creased with concern. “How do you feel?”
“Fine. Warm, maybe? It’s hard to tell.”
“Does it feel like One for All did?”
Deku shook his head, “not at all. Besides, if it was a part of One for All, wouldn’t I have felt it?”
The tingling through his fingers wasn’t the same kind of numbness that came from a flood of power. He wasn’t sure the power felt like it was in his hands at all. Whether this was a quirk, or an echo of One for All, the end result was the same. No matter where they came from, Deku still saw the strings.
Deku turned his hand over. Where other people had a thread, on his hand, nothing was there. “Whatever it is, I don’t think it has much use in combat. ...It could have a tactical application, though. They seem like they show up when someone–”
“Midoriya.”
Aizawa stood in the doorway. His voice crossed the room. “You’re late for class.”
The statement was so blunt, it took a second for Deku to understand the wrinkle in the logic.
“Wouldn’t you be late, too, then?”
It felt like a fair point. Aizawa didn’t move.
“No one else is in class,” he said. “Work studies.”
The understanding hit.
“Oh…”
Of course Aizawa had time to find Deku. There was no one else for him to teach. The curriculum at UA encouraged learning on the job and practicing hero work at real agencies. Agencies that, being quirkless, Deku couldn’t join.
Deku watched Aizawa closely, considering what, if anything, he should say. He faced Aizawa for so long, he couldn’t help but see his string.
The red thread on Aizawa’s pinkie wound down the hallway. Aizawa stood still. The thread shrunk. The other side was moving.
He could hear why.
“And here’s the brand new Science Lab, where our genius engineers and heroes alike come to build chemistry and make physics feel physical!” Present Mic spoke towards a crowd of cameras. “Our investment in top-notch tech is thanks to support from viewers like yours, and not at all because the last one exploded!”
The way Present Mic laughed it off, it was clear to anyone who heard him just how false that claim was. Only Izuku could see the string. The red thread on Aizawa’s hand stretched across the hallway, around the corner, straight to Present Mic’s pinkie.
It was the sort of thing Izuku hadn’t thought about before. Now that he could see it, he couldn’t stop. “Huh…”
“Huh, what?” Aizawa asked, clearly disinterested. Deku ignored the tone.
“Are you close with Present Mic?”
Aizawa looked away. “It’s not your business.”
“You’re not close to your boyfriend? That’s surprising. Should I tell him?” Toshinori asked, clearly kidding.
Aizawa didn’t take it that way. “It’s not his business,” he dismissed, stern as ever. Normally, that would be true. Where Deku stood now, it was.
As far as Deku understood their quirks, there was no obvious tactical benefit that tied Present Mic’s quirk to Eraserhead’s. The strings that Deku saw weren’t between the quirks, but their users. It was real compatibility, the tie of one soul to another, that only Deku seemed to see.
The instant Deku saw that, he knew what he could do.
“Can I start going to training sessions? I want to quirk analysis on the rest of the class.”
Aizawa looked at him suspiciously. The suspicion sank to exhaustion. “Fine. Knock yourself out. As long as it's not literally.”
Deku launched into a bow. “Thanks!!!”
The way Deku saw strings might not have been a quirk. It also might not last. Still, however long he could see these bonds for, he could use that sight to help.
The first time Deku went to observe, he meant not to intrude. Someone else observed him, first.
“Oh! Deku!” Ochako paused mid-float. Her hand launched up into a wave. The red string on her pinkie seemed to stretch on forever. “What’re you doing, here?” She asked with no judgement, only cheer.
Deku watched her string sway into the distance. Then, he watched her. He met her smile with a nod.
“I want to help!”
“Help with what?”
“Your quirk training!”
“Sounds great!” Ochako flashed a thumbs up.
Between the volume of the two of them, their other classmates started to notice. Tsuyu turned, next. “Izuku? What’re you doing?”
He took notes.
Quirk analysis came easily. Deku had come up with new strategies for quirk use before. It wasn’t the same experience as being in the training sessions himself, but observing to help his classmates and collaborate felt natural. Normal. Like he should have been in this room all along. What changed were the strings.
The longer Deku spent observing quirk training, the more bonds he was able to find.
Hagakure’s was tricky, but her string was still visible, even when she wasn’t. He could tell the third time he spotted it hovering that Ojiro was on the other side.
Other strings were even harder to track. Not every partner was in their class. Iida’s took a while to spot. His string ended in class B, with Kendo. It wasn’t a combination Deku would have expected, but he reported it anyway.
It took a few matches before Deku started to notice how much the bonds seemed to mean. It wasn’t just the user’s quirks that worked well together. The people did, too. It wasn’t just a bond of quirks. It was fate—a destined partner.
Why Deku could see them, he wasn’t sure. It wasn’t a quirk, exactly—or if it was, then it was one which wasn’t suited to hero work—but, it was useful.
He used it.
The more Deku took notes, the more he was able to notice not just the pairings, but his classmates themselves. His classmates’ quirks had gotten stronger. Each time they used them deliberately, Deku could see the strings clearly.
When every quirk was in use at once, they looked like a mess. The tangled mass of red might as well have been a ball of yarn. Most of the time, he couldn’t see where it ended… but once in a while, if they were in just the right pair, his classmates shared the same string.
When Deku noticed a bond between his classmates, he made a note, and gave a recommendation to Aizawa that the two be paired for missions. Sometimes it was intuitive. Others, less so, but the end results were the same. It took a few weeks before Deku noticed his classmates came back from those missions closer.
Deku never told his classmates about the strings. It was just nice to watch the pairs be happy. When their hands brushed close together, with the red string of fate taut and tight, they really did look happy. The happiness was so complete, it made him happy, too. It wasn’t the same as being a hero, but it was still helping. He would have thought it was a quirk—some last whisper of his borrowed power—if only Deku had a string.
Where everyone else in his class had red wrapped around their finger, Deku had nothing. It was just gone.
The only other problem in class was—
“No one’s left to train with!” Katsuki stomped up to complain.
Deku held his notebook tight. As much as he wanted to say it wasn’t his fault, that wasn’t exactly true. He scrunched down, instead.
“Some of the others don’t, either. You—“
“—You got a problem with me?” Katsuki barked in Deku’s face.
At that exact second, he did. Deku knew better than to say it. He also didn’t say no. The lack of a refusal was reason enough for Katsuki to get in his face.
“Don’t you get it? I need a partner for this!”
“Well. Ashido’s at her work study, so, Kirishima should–”
“Not that partner! A date!” Katsuki grabbed Deku by his collar, pulling him in. “Or did you not notice you hooked up half the class?”
The snap made Deku scrunch down. “You don’t have to say it, like–”
“Like what? The truth?”
The way Katsuki snapped it, Deku couldn’t find the will to disagree.
It took a second of silence before Katsuki would say it. “I got invited to this rookie to watch, golden guy banquet, whatever—“
“The Gold and Green Young Hero Banquet? That’s a big deal—!”
However Izuku tried to hype it, Katsuki’s glare didn’t change.
“Whatever it is, I’ve gotta bring someone with me. It’s plus one.”
Under ordinary circumstances, something like that wouldn’t be a big deal. Bringing someone to a party wasn’t much of an imposition, if the context were that easy.
A hero award was an honor, and, at this age, a business opportunity. Whoever Katsuki brought with him to something like that would be a reflection on him. Whether it was a date or a friend, they would have to match Katsuki’s image.
Katsuki hadn’t raised it as a question directly. Deku considered it just the same. He tapped his hand under his chin. “What about Kirishima? He might—“
“He’s busy,” Katsuki countered. “He’s always with Ashido.”
The way Katsuki looked at Deku while he said those words was just a clear message. He believed that Deku had something to do with Kirishima being busy.
Depending on how Deku looked at it, Katsuki wasn’t wrong.
“Sorry…?”
Katsuki’s expression sharpened, just short of a glare. He hadn’t said the word, yet the look on his face spoke for him.
Deku pointed back towards himself, understanding. He wasn’t sure he was right, yet he couldn’t help but check. “…You want me to help?”
Deku phrased it like a question. Katsuki didn’t face him that way.
Katsuki twitched. He stared forward, thinking.
The thought stopped just as quickly. Katsuki turned. “I shouldn’t have asked! You—“
“Wait, wait!” When Katsuki tried to turn, Deku pulled the other way.
“I’m not waiting!”
“We can run tests!”
“Testing what, my patience?”
“No. Your quirk!”
“What?”
Deku waited for the room to clear to explain.
Katsuki knew more than enough about One for All to catch onto this, too. As much as Deku could explain, he did. He laid out the conditions that would help him see the red string.
Deku had seen it enough times from afar to have a sense of what should be there. With Katsuki that much closer, Deku could get a better look. He’d never had someone show him deliberately.
Katsuki lined up a shot, and fired from his gauntlet. As the smoke was still clearing, he took the cuff off his right hand. Sure enough, at the end of Katsuki’s pinkie, Deku could see a frayed string. At least, he thought it was a string.
“What’re you looking at?” Katsuki snapped. Deku drew closer.
The red ring wrapped around Katsuki’s pinkie. A thread dangled from the edge. It fell. It didn’t look like any string that Deku had seen before. It had an ending. The edges were frayed and singed, as if Katsuki’s quirk blew straight through it.
“I can’t tell,” Deku admitted, his voice drifting into a mumble. “Something’s there, but I…”
The way Deku’s voice trailed off left Katsuki room to snap. “You could’ve said you didn’t want to! I’ll find my date on my own!”
Deku raised both his hands. “No! I mean, something’s there. I see it! I just can’t tell where it’s going. It–!”
“Then, follow it!”
“It— It doesn’t work like that—!” Deku stuttered. He looked down, knowing all too well it did, in fact, work like that for most of his classmates.
Deku had seen plenty of strings by now. Some of them went on forever. Others ended close by. A few seemed to have no string at all. This was the first and only time he’d seen a string have no ending.
Deku stuttered, trying to think. The most he managed was “I—“
“Just say you don’t want to!”
Katsuki slammed the door. Deku tried to reach out. “Kacchan—!”
He couldn’t say anything else before Katsuki slammed the door.
Deku’s hand stayed in front of him. He kept reaching. He saw his own fingers. Where a red string would have been, Deku only saw his scars.
Katsuki’s hand wasn’t like this. It wasn’t that Katsuki had no string. It was that the string was blown apart. Something happened to that string. Someone should be on the other side.
Deku did the only thing he could think to do. He pulled out his notebooks.
There were still some unmatched people in class. It wasn’t just Katsuki. He could try to focus on something instant, and pick someone else he hadn’t matched—or he could start investigating recent graduates and other schools. There were so many options, he wasn’t sure where to start.
Deku was so busy thinking, he didn’t notice Ochako sitting down beside him. She held out her bento. “Or, you could have a rice ball.”
The sound was so natural, Deku started to say it, too. “Or, I could have a—“
Deku caught his own words. “Uraraka—!”
Deku slammed his notebook shut. The pages ruffled over his face.
Ochako put her lunch box down. She scratched the back of her neck. “Whoops. I didn’t mean to scare you!”
“You didn’t,” Deku said, obviously scared. He held in his shaking, and shifted, desperate for a distraction. He swallowed the distraction. “Is it time for a snack?”
“If you want one.”
Deku hadn’t planned to look down. He couldn’t help it.
“That looks like lunch…”
“I haven't eaten yet! I’ve been pretty busy,” Ochako added. “You seem busy, too.”
Deku kept looking.
There was no string on Ochako’s finger. She must not have used her quirk recently. The times when Deku had seen it, he couldn’t tell where it ended. He’d never been able to give her a partner, either.
“That might work…” Deku muttered to himself. He wasn’t by himself.
“What’s wrong?” Ochako asked.
Deku raised his hands high. “I’m fine!”
The quick insistence left Ochako that much more confused. Her brow creased with concern. “You can still be fine, and have something be wrong.”
“I guess…”
However much Deku doubted it, Ochako didn’t. She held tighter. “It’s okay. Whatever it is, we can do it together.”
It might work.
Ochako and Katsuki weren’t tied with a string, but they would balance each other out. A rescue hero and a battle hero would get good publicity as a duo, too. It was a good combination for team up work. If Deku looked at the issue logically, pairing Ochako and Katsuki wasn’t a bad call.
“This might be a weird question…” Deku clenched his fist, hiding his fingers inside. “How would you feel about going to an event with Kacchan?”
“An event?” Ochako repeated. “You mean a mission?”
Deku shook his head.
“No. A… a party. He’s supposed to bring someone with him. I’m trying to find a good option for him.”
The more Deku tried to explain, the more he doubted it was a good idea.
Ochako turned towards him. “I could do it, sure, if it helps you… but I don’t think that’s what you’re thinking. Is it?”
When she asked so directly, Deku couldn’t find the will to lie. He paused.
“You’re a better option,” Deku said, instead. “You’re a hero. You should be doing stuff like that. You’ll need a network after graduation…”
It was logical. Reasonable. Ochako cut through his reason.
“Don’t worry! I’ll get sidekick offers. And if I don’t, I’ll make an agency on my own. If you want to go with Bakugo, you should ask him.”
The way Ochako said it, Deku couldn’t help but be baffled. “Wha–? Why would–”
Ochako clapped her hands, cutting him off. “Just think how many notes you could take! At a place like that, there’s bound to be tons of heroes.”
Deku sank into himself. His shoulders rose to his ears, shrinking away. “I can’t bring notebooks to a banquet. That’s so unprofessional. You need to wear a suit. Where would it fit?”
Deku’s words raced ahead of him, the syllables scrambling so tight together, Ochako could barely make them out at all.
Uraraka laughed. She handed him the rice ball. Deku held it in his hand, where there would have seen a string, if only he had a quirk to cause one.
Deku wondered what he would have told Kacchan, if he couldn’t see the strings. Maybe that was the answer he should have given. Maybe that was the person he should be—that if he couldn’t see the string, then fate didn’t matter.
He held his fist tighter, to make himself sure.
“You’re right, Uraraka. I should tell him.” Deku clenched his fist, covering his pinkie. Katsuki might not want to hear it. Still, Deku wanted to say it.
Ochako raised both her hands in victory. “That’s the spirit! Go, get him!”
Deku wasn’t so sure that it would work that well. Even so, he kept his fist high. He nodded in determination. “You, too!”
The second that he finished speaking, Deku realized his mistake. He froze. “Wait! Not like that! Get who you want to get, whoever that is! They’ll be lucky!”
However tense Deku sounded, Uraraka didn’t mind. She gave a thumbs up.
“You bet!” She wasn’t trying to show anything. She’d raised the wrong finger. Even so, Deku couldn’t help but to see. On the other side of her thumb, a narrow, red string stretched into the distance, somewhere far, far away.
There was someone lucky on the other side of that string. They just didn’t know it yet.
Deku closed his fist, too, covering the lack of his own. There was no luck for him to use. He held tight, anyway. There was nothing here to guide him, but he could always lead himself. He just had to try.
Deku marched through the halls and stairwells, straight to Katsuki’s dorm room. He didn’t wait for a sign. He just knocked.
“Kacchan!” Deku called out. “Kacchan!”
No one answered the name.
A light shone beneath the door. It was well after curfew. As far as Deku knew, Katsuki wasn’t on a mission, and it was way too too early to be asleep. He might not open the door, but he could hear.
“Me!” Deku shouted. “Take me! That’s what I think!”
There was no answer from the other side. Deku didn’t let that stop him. He pressed his hand against the door frame, and leaned in.
“I can’t be sure that I’m the right choice, but, I can’t see what your right choice is. All I know is that I want to be there, too! I–”
He would have had more to say, if only Katsuki was there to open the door. He wasn’t.
“What are you talking about?” Katsuki asked over Deku’s shoulder.
Deku’s heart skipped a beat. He turned. “Kacchan—“
“You heard me!”
Deku swallowed the obvious answer of Katsuki’s name. He turned towards the sound.
Katsuki stood on the other side of the hallway. A towel wrapped around his waist. They were supposed to have school issued bathrobes. That was far from the only issue at the moment.
Deku shook his head. He stood his ground, and knocked the doubt out of himself. Whatever nerves he knew he had, he gathered them to focus.
“Take me!” Deku held out his hand. His fingers stretched into the open. Where there would have been a string, his fingers were bare. He offered them just the same. “I can’t see a string, but I’ll hold on!”
“What’re you talking about?”
“I’ll go with you!”
Deku let his own hand down. He stared ahead, looking for something that wasn’t there.
He clenched his fist, covering his fingers with each other. It might not have been there, but it could be. “I checked my notes,” Deku added. “The statistical probabilities of finding a match outside of the classroom is—“
“Shut up. You damn nerd.” Katsuki cut in. “You can’t ask me out like normal?”
The snap was so abrupt, Deku almost didn’t catch the accusation. “Wha—“
Deku swallowed his stutter. He raised both hands in front of himself, and shook them away. “Who said this isn’t normal? This is normal.”
Katsuki stared closer. “Normal to who?”
They were so focused on each other, they wouldn’t have noticed Kaminari walk by if he hadn’t spoken. “What’s up? Lover’s quarrel?”
The way Kaminari spoke, he clearly meant it as a joke. Iida followed a step behind him. From the way he faced forward, it was obvious he wouldn’t have known a joke if it walked up and said ‘knock, knock’ in his face.
“As class representative, I must ask you to move any displays of affection inside,” Iida said in complete seriousness. His tone was so matter of fact, Izuku almost didn’t notice what he said.
Izuku pulled back and scrambled to speak. “I’m sorry. We’re not–”
The scrambling didn’t help.
Katsuki wrapped around Izuku, to clutch him that much tighter. He glared up at Iida. “We are inside. You see the roof, right?”
Izuku paused. He processed. At the end of the thought, his shoulders raised that much more. “You’re not gonna argue the other part…?”
Whatever confusion Izuku had, it didn’t go both ways. Katsuki huffed. “Why would I?” The snap of the question made the answer feel like it was meant to be obvious. It wasn’t.
Izuku looked back toward Katsuki. Katsuki did the same. Their hands stayed together, their pinkies interlocking. The way they crossed together, it felt a little like a string.
There may have been other people nearby, yet the way Katsuki looked at him, it was like no one else mattered, except for them.
“You have a suit?” Katsuki asked him.
“Like, my hero one? It might be in storage…”
“No. With a tie.”
Deku tensed. He paused. In a technical sense, he was in a suit with a tie right now. Their school uniform fit that description. Deku knew just as well that wasn’t what Katsuki meant.
Katsuki stepped into his room and didn’t look back. “I’ll tie it,” he added. “If you did, you’d make a lump.”
Deku lingered. He watched Katsuki cross through his doorway, unencumbered. At the end of his sight, he swallowed his nerves, centered himself, and looked at someone he never expected to see him quite so well.
“Kacchan?”
“What?”
Katsuki paused in his own doorway. He looked back.
Deku caught the eyes that met his own. He smiled.
“Thanks for inviting me.”
The second it was clear they’d found each other, Katsuki turned away. He huffed. “You invited you. I’m stuck with it.” Somehow, the snap in his tone made that sound like something he didn’t mind.
However this party turned out, or how poor of a plan this turned out to be, Deku knew there was no one else he’d trust more to fight fate with than the man in front of him. As long as Deku had known Katsuki, he’d known that Katsuki was too strong to shy away from a fight–and as long as they were together, they were worth fighting for. No matter what fate might have to say, they never needed a string to be together.