Chapter Text
1.
The first time it happened, it was Denki Kaminari’s fault.
Or Shinso Hitoshi's.
Probably both.
Izuku didn’t usually indulge in his friends’ antics, especially not on school nights. But ever since Todoroki’s dinner celebration brought the group back together, they’d started getting together more often, and Izuku found it harder and harder to say no.
Besides, since rejecting Katsuki’s invitation to join his agency, things between them had grown a bit… strained. Katsuki had started keeping his distance, a decision Izuku fully understood but couldn’t help despising. The unusual silence between them was suffocating, and even a flimsy excuse to be near Katsuki felt worth it these days.
Not that Izuku regretted turning Katsuki down, he knew it had been the right choice. Izuku had no business standing at Katsuki’s side anymore. He’d won the war, sure, but in hindsight, it really didn’t feel like a victory. Izuku had failed . Katsuki had been targeted for being the closest to him, and Izuku had failed to protect him.
Katsuki had died because Izuku hadn’t been fast enough, strong enough. Because he’d been too late.
Izuku didn’t think he could ever forgive himself. So, when everything came to an end, he embraced it with a heavy heart, convincing himself it was finally time to move on from his childhood dream.
Getting an armored suit in the process was definitely not on his bingo card, let alone the fact that Katsuki had been at the very heart of it. He still couldn’t wrap his head around how everyone had gone through so much trouble to create it for him. Every time he thought about Katsuki working tirelessly on it for eight years, his blood boiled, and his heart broke.
Katsuki needed to get over himself and stop chasing their childhood dream of competing with each other for the rest of their lives. Izuku had worked so hard to erase that idea from his own mind because it had been necessary— better for everyone . Katsuki was destined for amazing things. And Izuku? He just… wasn’t.
Sure, he still went on patrol once or twice a week, but that was the extent of it. He was in no condition to become a fully pro hero again, let alone join Katsuki’s agency.
No, Izuku didn’t deserve this. Katsuki would be happier and safer without him. It was only natural that he was keeping his distance a bit, these days.
Still, he kept asking and bringing up his offer, and every time, Izuku turned him down. Again and again.
“Have you reconsidered, nerd?” Katsuki asked that night, taking a sip of his beer.
Izuku was at the counter, elbows resting on the bar as he waited for his non-alcoholic drink. Even though they all had the next day off, Izuku still had to wake up early for school. Tilting his head, he met Katsuki’s gaze and offered him a soft smile.
“No, Kacchan, I rest my case. You know I… I’m happy doing what I’m doing,” he replied, though his fingers tingled with nervousness, and his chest tightened with anxiety.
He hated lying to Katsuki. Hated hurting him. But it was for the best. It had to be. Eventually, Katsuki would tire of asking.
“Okay,” Katsuki said, voice empty, grabbing his drink and marching off toward the group where the rest of their friends were standing and chatting.
Izuku returned to the table, sitting down next to Kaminari and Todoroki, the only ones left in the table. He barely registered their conversation, his attention drifting as his gaze inevitably found Katsuki a few meters away, now deep in conversation with Shinso.
“All I’m saying is he should give it a try!” Kaminari exclaimed. “Shinso and I have been together for a long time, so it’s not like that’s going to be a problem or anything. I keep telling him!”
Todoroki shrugged, noncommittal, and took another sip of his drink.
“We’re just looking for someone close enough to us so we can… you know, experiment with our relationship and have some fun. It’s not a big deal!” Kaminari continued.
That caught Izuku’s attention. His senses snapped into focus, and suddenly, he was very aware of Shinso Hitoshi leaning into Katsuki’s space just a few meters away. Shinso’s right hand rested lightly on Katsuki’s hip, his mouth suspiciously close to Katsuki’s ear.
“I hope he says yes!” Kaminari added, practically bouncing in his seat like an overexcited puppy. “Do you think he’ll say yes?” he asked Todoroki.
In front of Izuku, Katsuki shifted slightly, his body leaning back against Shinso’s front. Katsuki tilted his head, just enough to meet Shinso’s smoldering, tired eyes. Shinso’s hand didn’t move from Katsuki’s hip, and Katsuki’s expression softened in a way Izuku had never seen before.
And for some reason he didn’t want to unpack right now, Izuku saw red.
Katsuki’s hand came up to lightly grab Shinso’s where it rested on his hip, his touch deliberate and unnervingly gentle.
That was all it took.
A long forgotten power surged to life within Izuku suddenly, building in his core until it felt like it would overflow. He wasn’t in control. A faint crackle of ozone filled the air as familiar black and green tendrils of energy began to snake out from Izuku’s trembling hands. They moved of their own volition, sliding through the air like living things, and in the blink of an eye, they wrapped around Katsuki’s wrists and hips like vines, pushing Shinso back.
“What the fuck?” Katsuki barked, his eyebrows shooting upward in equal parts confusion and fury, his wrists now bound behind his back by the blackwhip tendrils.
The entire bar fell into stunned silence.
Shinso, wide-eyed, accidentally let his drink slip from his hand, the glass shattering on the floor as he stared at the unfolding chaos. Izuku, standing just meters away from a thoroughly livid Katsuki, looked like a storm personified, his breathing heavy, and blackwhip still crackling faintly in the dim light.
Shinso finally broke the silence with a dry laugh, “Yeah… what the actual fuck?”
˖˖˖⠀
Izuku was panting like a madman, his right hand still suspended in the air as Blackwhip kept Katsuki restrained.
When their eyes finally met, Izuku choked on his own spit, snapping back to reality as his stance wavered. His entire face flushed crimson, and the moment he seemed to realize what he had done, his gaze dropped to the floor, and the tendrils dissolved into thin air.
“Um…” Izuku mumbled, somehow managing to look bashful. Fucking nerd.
Katsuki angrily yanked his hands free the moment they were released from Izuku’s mysterious quirk and stomped toward him, shoving Shinso aside with his shoulder on the way.
“What the actual fuck just happened?” he demanded, grabbing a fistful of Izuku’s button-up, his knuckles white with tension.
“I—Kacchan, wait… I—I don’t kn—I don’t know, okay?” Izuku stammered, struggling to find his words as Katsuki hoisted him off the ground.
Katsuki clicked his tongue in frustration and shoved him back hard, sending Izuku crashing into the table behind him.
Why the hell had Izuku just used Blackwhip? How was that even possible? Had he somehow gotten OFA back and not told him?
Katsuki released Izuku with a snarl, storming past the stunned crowd and heading straight for the bathroom.
Shinso’s shameless, ridiculous proposal was the last thing on his mind now. Not that he’d given it much thought to begin with. Still, it had been… nice , in a way, to feel wanted. To toy with the idea of being desired, even if he was damn sure he’d turn them down, just like every other time they’d suggested something like that. It wasn’t his thing. Never had been, never would be.
Izuku came rushing after him, barging into the cramped bathroom just as Katsuki was about to slam the door shut.
“Kacchan, wait! I’m sorry, alright? I don’t know how… I have no ide–”
“I don’t fucking care. It’s whatever. Don’t fucking apologize, okay? You just caught me off guard, is all,” Katsuki snapped, splashing water on his face. Izuku hovered behind him, still blushing like a loser, visibly agitated.
“But I am sorry, Kacchan. I don’t know what happened. This has never happened before—I don’t understand…”
“This the first time it’s happened since you lost OFA, then?” Katsuki shot back, narrowing his eyes as he faced Izuku’s reflection in the mirror.
“What? Yes, of course! I would’ve told you if I’d gotten my quirks back, Kacchan!”
“Oh, you sure? I wouldn’t fucking know, Izuku! I don’t really know anything about you anymore!”
“Wh–What? What are you saying?”
“It’s nothing,” Katsuki gritted his teeth and forced himself to calm down. This wasn’t the time or place for this. “Just… fucking talk to All Might about this whole getting Blackwhip back all of a sudden, alright?” He turned around to face Izuku directly. “Something must’ve triggered it.”
Katsuki didn’t want to get his hopes up, but after seeing Izuku’s feral state back there and the look of utter rage he’d directed at Shinso… he might have an idea. A farfetched, maybe delusional idea. Could it really be…?
“Y–Yeah,” Izuku stammered, still leaning on the door and blocking Katsuki’s exit. “About that…”
“What could possibly trigger a fucking quirk you haven’t had for eight years to suddenly resurface, Izuku?” Katsuki snarled, shoving him against the door, his hand pressing firmly against Izuku’s chest.
“I–I don’t know, Kacchan…” Izuku stammered, still refusing to meet Katsuki’s eyes, letting himself be pushed further into the cold, unyielding metal door.
“Okay, then,” Katsuki snapped, stepping back abruptly. He grabbed the door handle with purpose, shoving Izuku aside in the process.
“Let me know when you fucking find out.”