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Growing up together gave Izuku a sort of…sixth sense when it came to Katsuki. His ‘Kacchan sense’ if you will.
He already considered himself a very empathetic person. Maybe it had to do with being an Alpha, the need to care for and protect those around him ever present. He was good at it too, good at reading people—their scents, their expressions, their posture—and figuring out the best way to comfort them.
Kacchan, however, didn’t have these cues, at least not as explicitly as others.
The Omega was always scowling, always slouching, always shouting. He closed off the rest of his emotions and only let his anger show.
One might think, how could Kacchan hide how he was feeling when he had little to no control over his scent? Well, for the safety of both the students and the staff at UA, everyone was required to wear suppressing patches over their scent glands.
Izuku had a sneaking suspicion that Kacchan would’ve worn these patches even if they weren’t mandatory, though. That was just how he was.
He’d be the first to tell you that he wasn’t ashamed of his status as an Omega, that he could surpass any Alpha hero out there—even All Might himself!
Ever since they were kids, Kacchan had said this to Izuku more times than he could count. He believed him—believed in him—every single time.
But even the strongest of pro heroes carried trauma with them, and Kacchan was certainly no exception.
-
Izuku could kick himself for not being quick enough, for not realizing what was happening sooner. It almost seemed to happen in slow motion.
From across the common room, he could see Kacchan sitting on a couch with his friends—Kirishima on his right, Sero on his left, and Kaminari dramatically sprawled across all three of their laps. Some of the girls were with him too, Jirou and Ashido both sitting on the floor in front of the couch. Ashido looked like she was getting really into whatever gossip she was going on and on about, but all of them seemed to indulge her.
Pack bonding at its finest.
Izuku’s attention flicked to the front door as it swung open to reveal the whole of Class 2-B. As they filed in for the impromptu Hero Course party, Izuku focused back on his own friends and tuned in just as Uraraka was animatedly telling a story from her current internship. How they had a run-in with a villain that had a quirk similar to Koda’s but with insects instead of animals. He laughed along with his friends at the way she shuddered in disgust just talking about it.
As usual, Izuku was physically unable to stop his attention from being drawn right back to Kacchan. Only he wished it hadn’t left him in the first place. If he hadn’t let his mind stray from the Omega, he might have been able to stop the hand that came down on the back of Kacchan’s neck.
He wasn’t sure what difference he could’ve made, but he should’ve done something . Should have protected him .
It was a friendly enough gesture—Izuku knew Awase had meant no harm by it, he couldn’t have known how triggering it was for Kacchan to have the back of his neck touched, especially when he was caught off guard. It was the same place that that villain, Dabi, had held him as he had been taken hostage, kidnapped by the League of Villains in their first year.
But the damage had been done, and Izuku could only watch helplessly as the consequences of it unfolded.
In a flurry of movement, Kacchan set off an explosion big enough to blast Awase into the nearest wall—and even sent his friends tumbling away from him—all whilst shouting, “Don’t fucking touch me!!”
As Kacchan gulped down air, his chest rising and falling heavily in his panic, his eyes darted around to assess the situation. Izuku could see the realization dawn on him by his single, faltering step backward, away from the mess he’d caused.
Without a word, Kacchan shoved his hands into his pockets and stalked off to the stairwell, bypassing the elevator, a scowl marring his features once again. He certainly looked as if he couldn’t be bothered to stick around all these ‘extras.’
But Izuku knew him better than that.
His hands were in his pockets to hide the way they were, no doubt, shaking. He chose to use the stairs because he wouldn’t be able to stand still in the elevator without his anxiety eating him alive. His scowl was his only excuse to glare at the ground so that no one would see the tears pricking at his eyes. And only Izuku would be able to detect the soured scent of his omega beneath his suppressant patches as he passed by him.
As much as he wanted to reach out right then and there to offer his comfort, he knew it would only cause Kacchan to break down in front of everyone. That would just make matters that much worse. So he bit his tongue and dug his fingers into his thighs to stop himself from doing just that.
Everyone’s gazes trailed after Kacchan long after the stairwell doors slammed shut, throwing the room into a stunted silence that no one seemed inclined to break.
“What’s his problem?”
Of course it was Monoma who would say something like that in this situation. Of all of the students in the heroics course here at UA, there were only two students—this blond Alpha with a raging superiority complex and one purple haired pervert of a Beta—who managed to get on Izuku’s nerves to the point where he felt the need to say, “Oh, fuck off.”
At that, everyone’s eyes tore from the stairwell to gape at Izuku because, let’s be honest, he almost never swore. And while his classmates had heard him curse occasionally, 2-B had certainly never heard him say ’fuck’ before. He rarely ever said it, never had the need to. Besides, Kacchan certainly swore enough for the both of them.
But could you blame him? He was pissed .
Izuku hopped up off the couch and stalked over to Monoma, finding pleasure in the several inches he had on him—Izuku happened to hit a hefty growth spurt between first and second year. He was sure he looked every bit the intimidating Alpha boyfriend that he was in that moment.
“I don’t want to hear it from you ,” Izuku growled, digging his index finger into Monoma’s chest. He knew his angry, protective pheromones were leaking from beneath his own, worn out scent patches, but he couldn’t be bothered trying to reign it in. “When you’ve faced an actual villain head on, one who has killed more people than you could imagine, who almost killed you , then you can talk. Until then? You can shut the fuck up.”
With that, Izuku shoved passed him, shoulder checking him hard enough that Monoma almost toppled over, and went over to help Awase up off the ground. He could hear Mina in the background yelling, “Pop off , Midoriya!”
Most of the students erupted into laughs and giggles and, just like that, the tension in the room was broken. Everyone then set about cleaning up the mess that Kacchan’s explosion had made. There wasn’t much left of the couch that he and his friends had been sitting on, most of it strewn in little pieces across the common room.
“Hey, I want you to know Kacchan didn’t mean to do that,” Izuku said, low enough that only Awase could hear him. “I want to apologize to you for him because I know he’ll be too embarrassed to.”
“No, dude, it’s okay,” Awase said easily, waving his arms in front of himself. “We all have some baggage we’re carrying and I should have been more considerate. I probably should have been a little smarter about sneaking up on a future Pro Hero the way I did. His reflexes are fast as hell, though, I barely even had the time to react before my back hit the wall.” The two of them chuckled before Awase continued, “Seriously, though. There’s no hard feelings, and tell him I’m sorry too.”
“Will do,” Izuku smiled. “Enjoy the rest of your night.”
As much as Izuku felt like he should stay down here to help clean up, he couldn’t ignore the itching in his brain that he needed to find Kacchan. His omega was in distress and he needed to protect him.
Logically speaking, Kacchan could physically protect himself just fine all on his own. But emotionally? He was a little challenged in that regard and most definitely needed Izuku’s help with it.
He bid everyone a good night, gave a general apology about the mess, glared daggers at Monoma one last time, and then made his way over to the elevator. Knowing Kacchan, he wouldn’t have gone to his own bedroom so Izuku pressed the button for his floor.
Upon entering his room and flicking on the lights, Izuku immediately noticed that all of his blankets and his All Might themed comforter were missing from his bed, which was to be expected. What he hadn’t anticipated, though, was the trail of clothes leading from his open dresser drawers and his laundry basket over to his closed closet door.
After shutting and locking the door to his bedroom, Izuku walked over to his closet. He rapped on the door softly before opening it slowly. The light bleeding in from his room illuminated a figure huddled up in the back of the closet, wrapped up tightly in Izuku’s blankets and surrounded by a massive nest of what looked to be nearly all of Izuku’s clothes.
Little sniffles filled the silence and Izuku’s heart just broke at the sight. As quietly as he could, Izuku shut the door, throwing them back into darkness, and shuffled blindly toward the soft, pitiful whimpering. He swiftly peeled off the patches on either side of his neck as he went and let his soothing pheromones fill the small space.
As soon as his hands met Kacchan’s form, he maneuvered the omega to straddle his lap so that he could press his nose into the crook of Izuku’s neck comfortably. He held Kacchan securely in his arms because, as much as he wanted to soothe him with comforting words, he needed this more.
Slowly but surely, Kacchan’s sniffling died down until it dissipated completely, leaving Izuku with a cuddly Omega contentedly nuzzling into his scent glands. The relief Izuku felt, having successfully soothed his future mate, was insurmountable.
“Awase said he’s sorry,” Izuku whispered into the darkness. “Said your reflexes are ‘fast as hell.’”
That earned him a weak laugh, “Maybe his reflexes are just shit.” Kacchan’s grip on him loosened slightly as he continued to calm down and relax in his Alpha’s arms.
The light mood didn’t last long and Izuku nuzzled into Kacchan’s neck as well.
“That was a bad one, huh?” Izuku murmured into his skin. “I’m sorry I didn’t get up here faster. You even had to use my dirty clothes for your nest.”
“It’s fine. I still could’ve handled it without you,” Kacchan muttered, but the way his grip on Izuku tightened again told a different story. “Your nasty ass sweats enough that your dirty clothes smell just as strong as your neck. Maybe even stronger.”
“Whatever you say, Kacchan,” Izuku chuckled softly along with his omega.
Another few minutes passed before Izuku broke the silence once more, “You want to get ready for bed? We can sleep in here if you want to.”
“Yeah, let’s go.”
And because Izuku always managed to take forever in the shower and doing the rest of his nightly routine, Kacchan finished much sooner. He disappeared for a while and, just as Izuku finished up, appeared again to drag Izuku back to his room by the wrist.
As they walked into the closet, Izuku noticed that Kacchan’s nest seemed much more organized now, every article of clothing meticulously placed, each blanket weaved in with intent. It had been haphazardly thrown together in Kacchan’s haste to self soothe before, a valiant attempt to avoid a full blown panic attack.
A single pillow was placed at the top and the blankets had been pulled aside to allow the two of them to crawl in. Izuku laid down first, opening his arms to beckon Kacchan to lay beside him.
But Kacchan only stared at him with furrowed brows.
“You’re in the wrong spot,” he said at last.
Izuku stared back in confusion for a second before realizing that, duh , of course Kacchan would want to be between him and the wall. It would make him feel more secure. So Izuku shuffled to the other side, taking care not to disturb the walls of his nest too much, and then patted the open spot beside him.
“No, that’s wrong,” Kacchan pouted, irritation rising in his voice.
He kneeled beside his nest and pushed Izuku right into the middle of the space. “Like that.”
“But Kacchan, that doesn’t leave any room for— oof ,” Izuku grunted as Kacchan all but flopped down onto his chest. He shoved his nose into Izuku’s scent gland and almost instantly started purring in content.
And when has Izuku ever been able to tell Kacchan no? All he could do was pull the blanket over both of them, wrap his arms around his precious Omega, and settle his nose into soft, blonde hair.
So maybe his Kacchan-sense wasn’t accurate 100% of the time, but he came pretty darn close. After all, no one else knew his best friend—his future mate—better than him.