Aizawa sighed into the his scarf, watching the kids warm up. As always, keeping several of the class focused on their stretches was an exercise in futility. While Bakugou was doing a good job of hiding it Aizawa could tell the boy was floundering at not having his usual warm up partner. Kaminari having to suffer in Kirishima's usual place. The electric blond was taking the abuse with minimum whining, still distracted by the news of his possible future. Aizawa wondered if he should say something, but ultimately decided against it.

Being a hero may be presented as a glamorous, adventurous life to the public but the gritty reality wasn't going to change. If Kaminari faltered at hearing his alternate reality counterpart got injured on the job, then the boy might need to be looking at a different career. He would see much worse than that, Aizawa was sure.

The rest of the class was working hard to maintain their usual cheer. Curiosity dampened for the time being but there was a charge hanging in the air. An excitement. Aizawa had no illusions that todays training was going to go wildly off schedule.

He flickered his eyes towards the cause of all this. The older Kirishima standing relaxed at his side.

The man was grinning, looking out over the kids with something like nostalgia. He laughed as Sero triped Ojiro with his tape, sending him tumbling into Tokoyami, who then fell over Dark Shadow into Shoji. Aizawa sighed, pinching the bridge of his nose. He knew his kids had talent, that they were going to be great pro-heroes one day, but sometimes it was hard to see them as anything else but the clumsy teenagers they were now.

"Oh man, that was good" said Kirishima, wiping away a tear of laughter from his eye. He met Aizawa's gaze, giving him a commiserating look. "Still got a long way to go, eh?"

Aizawa huffed, "You can say that again."

Kirishima continued to look at him, assessing. It was a strange experience for Aizawa, not used to being scrutinized so closely by someone he considered a student.

While the man was obviously a much older than his student he was also still so very clearly Kirishima, but the air he held was different from the clumsy, honest sincerity of his teenage self.

It was the confidence. The experience laying over him like a second skin. Heavy, but comforting. A weighted blanket of reassurance and safety.

It was exactly how a pro-hero should be.

Well, at least Aizawa could be sure he did right by at least one of his kids in the other reality.

Kirishima turned his gaze away, focusing back on the kids. "Seeing everyone like this makes me realize just how far we've come. I just-I can't get over how young everyone is. Heck, Ryusuke's older than them. He's going to graduate in a few months. And then he's going to be out there. Really out there. Facing down villains and dealing with disasters like we were." The redhead took a deep breath, eyes crinkling just slightly, hands flexing. "I can't help worrying, you know. I don't know how you do it."

"Well, its not exactly the same," drawled Aizawa.

"Oh, come over teach. We all know you're a big softy," Kirishima grinned, nudging Aizawa in the side conspiratorially.

Aizawa blinked at the familiarity, so different from the way the young Kirishima treated him. This shift in power was throwing him for a loop.

"I'm not soft" Aizawa mumbled into his scarf, feeling called out. So what if he cared about this batch of students maybe a bit more than he should? With the number of problem children in their ranks he couldn't help getting move involved. God knows what they would get up to if he didn't.

Aizawa frowned, something coming to mind. "Wait, I thought you said your son was six? So who's Ryusuke?"

"Huh? Well yeah, the youngest is six. My oldest son, Ryusuke, is nineteen. He's graduating from UA heroics in a few months. His older sister's already studying at Tokyo U. Pretty sure thats step 4 on her plan to take over the world, or at least Japan." Kirishima shrugged ruefully, pride, love and affectionate exasperation literally dripping from his overly broad shoulders. "Me and Katsu are basically following an 'ignorance is bliss' policy on that one. As long as she doesn't do anything to extreme before we retire, it's someone else's problem."

Aizawa looked at the man, raising one pointed eyebrow. "You and 'Katsu'?"

The redhead paused, then flushed, rubbing the back of his neck bashfully. "Arg, damn. I'm not good at this."

"Being discrete never was your strong point," Aizawa pointed out dryly.

Kirishima snorted. "You can say that again. Katsu says I'm as subtle as a brick to the face. Which, to be fair, isn't too inaccurate a description."

Snorting softly in humorous agreement Aizawa blew his whistle, waiting for the kids to get themselves in order. They shuffled in closer, ready to hear what they would be doing today. Several expectant gazes landed on Kirishima.

Aizawa opened his mouth to start issue instructions when another thought sprung to mind. Perhaps unwisely, he let himself succumb to curiosity where teenage ears could hear. "Wait, if your oldest child is in university, and your youngest is six -just how old are you?"

Kirishima smiled, sharp teeth flashing and flexed one arm, the veins standing stark on his biceps, figure full of thick corded muscles encased in smooth, tan skin.

He pounded his chest with pride. "Fifty-one years young!"

"Fifty-one!"

The cry was from Ashido but Aizawa echoed her surprise. Kirishima certainly didn't look fifty-one. Not with that physique and flawless face. There wasn't a wrinkle anywhere on him. Not a single inch of sagging skin. The roots of his hair were as coal black as they ever were.

"Wha? But how! I thought you were, like, thirty!" screamed the acid user, several of the other students letting out their own cries of outrage. Aizawa kind of wanted to join them. He was only thirty-four and already had crows feet stretching from his eyes, gray hairs growing in around his ears. Just how was this fair?

"Fifty-one" coughed All Might, having been listening nearby. "And you still work as a pro-hero?"

"Yep. Mostly just on call, but I fill in every now and then. It was why I was on the sofa last night. Possibly why my son was troubled too. It was a pretty big fire I had to deal with, I imagine it was on the news. He's sensitive to these things."

"Man Kiri, are you sure that's safe? Shouldn't you be, like, retired by now or something? What if you get hurt?" said Kaminari, rather tactlessly.

"Statistically, very few pros continue to work past their forties" muttered Midoriya, flickering is eyes to All Might.

"Retire?" said Kirishima slowly, like the idea had never occurred to him. "You think I need to retire?"

Aizawa sighed, recognizing that slow spread of teeth as the challenge it was. No use trying to stop the train wreck now.

Kaminari shuffled nervously, "Well, I just mean, fifty-one man…what if you get hurt? Or, like, break a hip or something?"

"Break a-" barked Kirishima in disbelief, the flames or ire beginning to flicker in his eyes. "What a load of-I could take on all of you right here, right now, and not break a sweat. Break a hip my-" he trailed off into grumbling. Crossing his arms with a huff and muttering about the disrespect of youth and whatever happened to respecting your elders anyway?

Of course, having thrown down such a challenge there was no way the students weren't going to pick it up.

Unsurprisingly Bakugou was the first to step forward, hefting his gauntlets and and biting at the bit to use them. "Hah!? Give it up grandpa! I'll fucking kick your ass!"

"Is that so" said Kirishima mildly, stopping his grumbling and uncrossing him arms. Letting his large hands hang heavy by his side. "Is that a challenge, Katsuki?"

"It's a fucking promise, Grandpa" snarled Bakugou, pops and crackles appearing around his hands.

The other students moved apart, getting into ready positions. Waiting from someone to make the first move.

Twweeeeerrrppppppp!

The mournful wail of Aizawa's dying whistle cut the tension.

"If you're done" said Aizawa. "Since it appears you all think that youthful enthusiasm is enough for you to defeat a seasoned pro-hero, despite everything you've been through already." He glared at the class, disappointed in them and fed up with their bullshit. A reality check was clearly needed. "All against one, bring him down in 20 minuets or you lose. Is that acceptable?" asked Aizawa, addressing the older man.

Kirishima cracked his neck, shucking his shirt with an obscene flex of iron hard abdominals -truly, truly unfair, thought Aizawa- he smashed his knuckles together in his signature move, smiling faintly.

"Sounds fine to me. I won't even move my feet."

At that declaration there were several excited mutterings and cries of decent. No one in class 1-A being able to take the clear dismissal of their skills lying down. Even the normally calm students, Shoji and Asui, looked faintly ticked off at Kirishima's taunting.

"Alright, if everything agreed, get into position." Aizawa placed a palm on Kirishima shoulder, getting his attention while the rest of the heard was moved off by All Might to the middle of the training ground.

"Let me guess, you're gonna ask me to not go too hard on them?" said Kirishima.

Aizawa faintly raised one eyebrow, a glint coming to his eye. "Actually, I was going to ask you to properly cut them down to size. Show them exactly what an experienced pro can do."

Kirishima flashed a truly alarming amount of teeth, shoulders flexing. "Gladly."

How dare those cretins call him old!? He thought. They were barely out of nappies! Time for a light warm up.

—

Katsuki bit his lip, watching as Kirishima came to stand in the middle of the loose circle of students. His eyes took in the differences between the older man and his Kirishima, picking out the unfamiliar scars, tracing the edges of those greater muscles, the easy relaxed stance. Watching the flex and pull of those pecs and abs as Kirishima quickly warmed up.

Fifty-one and the man looked like a thirty year old body builder. He would be a picturesque Adonis if it wasn't for the few scars scattered over his frame. A nasty scrape on his shoulder, a bumpy old burn on his side, a gnarly scar on his stomach, badly stitched together but faded with age, dark brown against his tan skin.

Katsuki swallowed thickly, dragging his eyes away with difficulty. Three decades of hero work was…a really good look on him.

Kirishima crouched down, quickly etching a sloppy circle into the ground. Only just about large enough for him to stand comfortably in with his legs braced.

"So, here's how this is gonna work" said the redhead, cracking his neck one last time and flashing them all a toothy grin. A dangerous, amused glint came to his crimson eyes. A shiver skirted down Katsuki's spine, his palms already sweating. Something electric hung in the air, his instincts crying out to run. That he was facing something dangerous. A predator. Fight and flight his only options.

Of course, Katsuki would never choose anything but fight.

"I'm gonna stand in this circle," Kirishima continued, pointing to the freshly carved line at his feet. "You lot have to either take me down or make me step out of it in twenty minuets. Starting when Aizawa blows his whistle. You can use any means you can think of. Nothing is off limits."

Kirishima paused, flickering his eyes from one student to the next. Pinning them with his blazing stare. He flexed his hands, hardening creeping across the palms, curving his nails into talons and serrating his forearms.

Kirishima banged his fists together and Katsuki felt his heart give a solid thump as adrenaline flooded his veins. The sound echoed, loud and surprisingly menacing. Kirishima's grin grew larger. With every new pointed tooth uncovered the tension grew thicker.

"I suggest you don't hold anything back. This will be really boring if you do."

Katsuki snarled, listing to the old bastard taunting them like they were children. Katsuki was going to fucking own his ass. He was going to blow him to hell and back. Then he'd see how easy Kirishima found it to laugh at him.

"You heard the rules. Get ready," said Aizawa, lifting his whistle to his mouth.

Tweeeerrrrppppppppp!

Katsuki lifted his arm and pulled the pin, opening with a full powered howitzer shot. The explosion rolled fourth, consuming everything in it path. A tsunami of heat and light.

Several students had to quickly jump out of the way or risk getting consumed. The noise felt like god descending on the training ground, shaking Katsuki down to his bones and lighting his blood on fire. A feral grin of victory curled at his lips.

"Fuck! Dude! Kaminari was behind him!" shouted Sero, having swung himself away on a safety line and picked up Jiro on the way. He and a few others were glaring at Katsuki. He snarled at them, flipping them off. Like any of them were going to be able to take Kirishima down. It's not his fault if they couldn't move their asses quick enough.

"Ahh, that's nice," sung a voice. An aggravating, cheery, deep baritone voice.

Katsuki's eyes flew to the center of the explosion, watching a silhouette appear in the heat haze. Standing tall and unbothered in the raging inferno.

Kirishima smiled at him, hardened teeth jutting monstrously from his face. Every inch of his skin was cracked, crevasses and lines of hardening stretching over his chest. Outlining every muscle in high definition.

It looked like Unbreakable, but the man stood loose and relaxed. Nothing like the tense, frantic energy of the Kirishima Katsuki knew. This Kirishima wore his ultimate move like a second skin. Like he didn't even notice the calcifying of his body. Unbreakable no more effort than breathing.

Soot was gathered on his shoulders, and his pants were smoldering but Kirishima looked no more phased by the explosion than he would by a summers breeze. His feet had not moved a single millimeter.

He winked at Katsuki, "Thanks Katsu, I needed to warm up. Get it, warm up? Hahaha!"

Katsuki felt his eye twitch, feral smile shrinking a few molars as his glare intensified. The other students looked at Kirishima and gulped, realizing they may have bitten off more than they could chew.

Kirishima shook his arms out, hardening rolling over him in waves. A second there, another second not, until it settled into a comfortable middle ground. Arms, shoulders and chest armored, face cracking around the edges but lips left loose enough to talk properly. His mane of hair clattered together, stalactites smashing against each other as he turned his head.

He held up a forearm across his chest, hardening shifting and settling, compressing.

"Well then, my turn."

Crack!

It was a small sound, sharp. If it wasn't for the silence Katsuki probably wouldn't have even heard it.

The effect was huge.

Something hit Katsuki in the stomach, blasting the breath from his lungs, pulverizing his intestines and having bile racing up his throat. Katsuki went flying back, bouncing across the ground as he did so, mind white with the pain.

His vision swam, black spots dancing in his view. He chocked, spittle flying from his mouth as he desperately sucked in short, sharp breaths to stay conscious.

"Holy shit!" someone cried distantly.

"The fuck!"

"Kacchan!"

"Pay attention!" snapped Aizawa, reprimand cutting through the students shock like a knife.

There was another muffled crack and a squeak as Sero and Jiro flung themselves to the side. The invisible attack caught them on the ankle, sending them spiraling across the ground. Only when they scrambled to their feet did Jiro discover the attack was aimed at her boots, having completely shattered her jacks, and thus severally limiting her combat abilities.

"Spread out, pull back!" shouted Todoroki, sliding away on his ice. Katsuki blinked his eyes, dragging himself on the ground and lifting his head with monumental effort. His vision was blurry with tears, his mind hazy with pain, but he made himself pay attention. Heaving in long, slow breaths, stomach and chest burning with pain. His legs trembled, weak. He gritted his teeth, tasting blood.

It tasted like failure.

The would be heroes drew back, all fearing another devastating attack by the redhead. Their eyes restlessly moved as they sought to understand just how the man was attacking them. A sense of danger descended, any spark of humor killed in an instant.

Kirishima relaxed his arm, taking a deep breath and smiling at all of them. He scratched his ear sheepishly.

"Ah, whoops. I might have gone a bit too hard there. My bad. Is Katsuki alright?"

Katsuki made a fist, banging it on the ground, but no matter how his mind raged his lungs still screamed and his abs felt liquidized.

"He'll live" said Aizawa, voice cutting and tense. "How did you do that?"

Kirishima shook himself out, stretching out an arm in demonstration as his Quirk sprung to life at his will. "Compressed the air between layers of my hardened skin. Take it to the limit and then purposefully create a fault line down the outer layer at the same time as expending the inner layer, firing the compressed air outward. It takes a lot of control, and was freaking messy to learn I can tell you. But, by now-" Kirishima shrugged, hardening rippling rhythmically down his arm, cracks appearing and closing in seconds, taking in and loading another shot of air. Compressed and ready to fire. "It's pretty much instinct."

Katsuki stared at the man, the students stared at the man, Aizawa and All Might stared at the man. Seeing their pale faces, their terrified stares, the redhead shrugged ruefully, flashing his fangs.

"What? I had to solve my mid-range problem somehow. You should see what I can do if I go Plus Ultra and use my blood instead. Liquids a lot easier to take to pressure extremes and a lot more destructive when fired. I can really ramp up the piercing power."

Kirishima sighed regretfully. "But Katsu says I'm not allowed to use that move anymore without permission." The redhead pouted, lowering his weaponised arm and looking entierly like a reprimanded toddler.

"Honestly, you slice off a mountain one time…"

Silence. Cold sweat cascaded down Katsuki's back. What? A mountain? Slice off? A mountain! Just what the fuck had Kirishima become? At what point did his Kirishima, the far too sincere, kind of goofy, overly cheerful dumbass obsessed with manliness, become this!? This utterly terrifyingly competent fighting machine. Just what kind of villains had he faced to need such moves?

"Ahem" All Might cleared his throat wetly, capturing their attention. "Maybe you could avoid using such attacks for now. Give the students a chance."

Kirishima shrugged, releasing the pressurized air from his arm into the ground. Cutting a line in the floor between Shoji and Tokoyami's feet. Dark Shadow squeaked, pulling back.

"Sure. I'll stick to close range, shall I? Do you want to restart?"

"That might be for the best" said Aizawa. "Alright, everyone back in position. Same rules, but Kirishima will stick to close range combat only. Bakugou, can you continue?"

Katsuki grit his teeth, bitting into his lip and slowly sitting up. His stomach revolted, nausea sweeping through him, but he refused to sit out. Forcing the sensation down with will power alone Katsuki stood up, knees shaking, abs screaming. Black spots spotted his vision. He told himself that it was just his sweat making his eyeliner run.

Aizawa looked him over carefully, hesitating. Katsuki glared at him. The mans shoulders slumped. "Have it your way then. Everyone ready?"

The students gathered back into their loose circle, looking considerably more tense and pale compared to last time. There was a palpable feeling of fear in the air.

Kirishima bit his lip, contrite. He hadn't actually wanted to hurt anyone. Just, scare them a little. Make them regret calling him a grandpa. He'd have to be more gentle.

Tweeeerrrrrppppppp!

—

Eijiro sighed as he chucked Ojiro away by his tail, ducking under Midoriya's swing and standing firm as Ida kicked his shins, his armor crumpling and foot jarring for the effort.

He nibbled his lip, feeling guilty. He should have known that Bakugou wouldn't have been prepared for his air cannon attack. Should have lowered the damage output. He was just so used to sparing against his Katsuki, with his near inhuman reflexes and endurance built by years and years of training and hero work.

Obviously Eijiro cold see Bakugou wasn't his Katsuki, but even though the teenager was more emotionally unstable, more vulgar, more angry than his Katsuki, less content in his own skin, he was still so obviously his husband. Everything that he loved about Katsuki he could see in Bakugou, everything about the man he was going to become started from that angry, raging teenage boy.

Eijiro had maybe wanted to show off a bit. Impress the blond. It was pretty sad, he should be more mature, more in control of his impulses. Just, when it became clear earlier that the Kirishima and Bakugou of this reality weren't together, that maybe they didn't even have those kinds of feelings for each other, he had been a little disappointed. A little angry.

Frustrated.

So he had wanted to show off a bit. Prove just what he could become, just what this realities Kirishima could become. Because he was proud of his progress, and he knew Katsuki was too, and he was just so happy. So very happy with how his life had turned out, even though there had been tough times, sad times, soul shatteringly bleak times, he was happy. And a big part of that happiness was Katsuki.

So if he had maybe wanted to show the blond just what he might be missing. To make him really look at Eijiro, at his Kirishima…

Well, he had certainly done that. He wouldn't be surprised if Bakugou didn't decide to take his revenge on this realities Kirishima when he returned.

Eijiro winced just thinking about it, hardening his skin and spiking his blood on his his leg just before Tsuyu tried to wrap her tongue around it. She flinched, quickly trying to draw back the whip like appendage but he grabbed it, swinging the girl into the invisible Hagakuru trying to sneak up on him from behind. With his other arm he chucked Shoji over his shoulder into Dark Shadow.

Slicing away Sero's tape and feeling the fizzle of Kaminari's electricity harmlessly bounce off him, Eijiro sighed once again. More than a little bored. This fight was really driving home just how young everyone was. How inexperienced.

Ashido's acid fizzled away on the ground, failing to make a mark on his skin. He hardened the inner parts of his ears, Jiro's sound waves doing nothing to effect him. He grimaced as Mineta stuck another one of his stick hair balls to him, shedding the epidermis of the effect skin to unstick the thing and chuck it under Koda's feet.

"Stand back!" commanded Yaoyorozu, before a loud 'bang!' sounded.

Kirishima hardened his chest a tad more, leaning forward slightly to keep his balance as the cannonball thudded into him. The metal crumpled to the floor, ineffective. He brushed himself off, giving the frowning girl a cheeky wave.

A wave of fire surrounded him, cutting off his vision. Eijiro waited patiently, slightly excited. Thinking that one of the class would use the opportunity to plan some interesting strategy. Instead Todoroki flew through the flames, trying to grab him from his blind spot. The boy thrust his left side towards Eijiro's head, the flames extinguishing. Eijiro blinked at him placidly as the temperature rapidly dropped.

"Freeze" growled Todoroki, a wave of super cold air erupting around the two. In a second Eijiro was encapsulated in a small glacier, ice spikes rising his into the air. He could feel Todoroki's power trying to push further, to freeze the plasma of his blood and the water in his cells, but Eijiro hardened an inner layer of skin, trapping his own heat inside and keeping the cold out.

Within the glacier he blinked granite hard eyes, scraping the ice away. Through the blue tinted distorted world he watched dispassionately as Todoroki heaved in huge breaths, hands on his knees. Cold puffs of air escaped him as he used his fire to try and keep his temperature up. There was muffled cheer from some of the class.

Eijiro almost felt bad for what he was about to do.

Almost.

He tensed, and flexed.

There was a crack, a creak, and then an spin chilling crash as the glacier shattered from the inside out. The white of Todoroki's eyes showing as Eijiro shook the icicles from his shoulders. Lazily, he grabbed a falling ice dagger and threw it at the boy, aiming slightly to the left just in case. It flew straight and true, embedding into a boulder just behind Tosoroki's left ear.

There was a number of curses from the class.

"Half the time. Ten minuets to go" said Aizawa monotonously from the side line.

Eijiro looked around, gloom settling over the students. Giving up already in the face of the overwhelming power difference. None of them looked eager to approach for a second go.

Well, that wouldn't do. No point in sticking to close combat if the kids weren't going to try and attack him. Eijiro concentrated, gathering what felt like the 'power' of his quirk in his right leg.

He lifted his foot, taking one single heavy step forward, just within the bound of his circle. He released his quirk, sending it in waves to the bottom for his foot, rapidly hardening and expanding his skin several hundreds times in that second.

The energy rippled outward, floor vibrating and cracking, throwing several of the class off their feet. Too easy.

There was a flash of green electricity, Midoriya bouncing through the ruined terrain. His eyes were partly crazed, teeth grit in effort, arm drew back to punch. The light of full cowl shrouded him in ominous energy. With frightening speed he closed the distance.

Eijiro clicked his tongue.

He hardened his calves, bending at the knees and letting that overpowered punch sail over his head. His own taloned hand closed around Midoriya's wrist with a crushing grip. He spun the boy, bring him around and close to his chest as he straightened. The teenager adjusted quick, lashing out with a kick. Jarring his ankle against Eijiro immovable side.

Eijiro moved to restrain the boy further, but an explosion erupted against his spine. It wasn't enough to make him loosen his grip, not really, but it did grab his attention. Eijiro let Midoriya go, interested to see what Bakugou had for him next. The blond had been quiet so far, catching his breath.

Now Bakugou stood facing him with blazing red eyes, palms smoking and a thirst for revenge written clear across his face.

Eijiro felt fondness well within him at the sight of that pissed off glare. The furrow in that brow, the way Bakugou snarled on the right side of his face. The way those shoulders tensed in preparation to attack. The way somethings never changed.

"Die!" Bakugou screamed, launching himself through the air towards Eijiro. The redhead suppressed a sigh of disappointment.

One thing that had changed through the years, beaten out of him by necessity and age, was the blond's red hazed recklessness.

The explosive hero in training fell upon Eijiro. Keeping to the air and peppering explosions over Eijiro's back, always aiming for his blind spots. Using a flash grenade to try and white Eijiro's vision and make him stumble.

Eijiro hardened his eyes, fracturing his vision and reducing the shock of the bright light. Midoriya tried to come at him from the side, but had to somersault out of the way when Bakugou switched tactics. Aiming at the ground around Eijiro's feet to try and disrupt his balance. At last, some smart thinking.

Not that it was going to work. As someone who withstood attacks for a living keeping his balance was a must. After three decades of hero work Eijiro could balance on a landslide, let alone some fractured concrete.

Midoriya tried to move in again, full cowl coating him and a shout erupting from his mouth. Eijiro frowned, knowing the boy was pushing himself to the limits while Bakugou uncaringly continued on with his own attack. The both of them relying on simply overwhelming their opponent with power rather than working together. No discussion, no strategy.

No hope of success.

Now feeling a bit ticked off Eijiro pushed himself into Unbreakable, judging it enough. His form erupted into spikes of flesh, a mountain range of crags rising from his spine. His mane was a forest of stalactites, his mouth a maw of serrated teeth, the interlocking segments of his chest rubbing and clashing against each other like the coming together of the continents.

The blow landed on his shoulder, Eijiro swaying with the force just enough to stop Midoriya from shattering his whole hand. Though he was pretty sure he heard a knuckle or two crack. Katsuki's AP shot ricocheted off his left pec, the following off his abs and the third off his neck. All of them completely unfelt by the pro-hero.

Eijiro grabbed at Midoriya, grip unrelenting, and threw the boy with force into the flying blond.

"Fuck!" Bakugou shouted, going down in a tangle of limbs and cursing.

"I think that's enough" said Eijiro.

"I'm not done yet!" raged Bakugou, getting up again and firing off another attack. Eijiro let him, feeling the explosion breeze against his skin. Bakugou aimed for his face, Eijiro swiped away his hand. He aimed for his side, Eijiro trapped the palm between his elbow and ribs and used it to yank the blond off balance. The teenager spun, shoving his gauntlet as close as possible to Eijiro's mouth and pulling the pin, grinning savagely all the while.

Eijiro twisted his head, biting through the metal and releasing the nitro inside. Chucking Bakugou away just in time as the unstable liquid exploded, and wiping the soot from his chest afterwords.

"Katsuki! Stop it. You're going to hurt yourself."

"Don't call me that!" snapped Bakugou, struggling to his feet. His palms were smoking, twitching. His shoulders trembled faintly, having had to brace himself against too many big explosions in too sort a time.

"You're exhausted Katsu. Know your limits."

"I told you to stop fucking calling me that! I'm not your fucking Katsuki. I'm not some fucking weak ass second place! I'm going to be number one!"

"And you will be, but this isn't the way to go about it. Hurting yourself won't make you stronger."

"The fuck do you know!" spat Bakugou, face twisted in rage. He released his gauntlets, one broken and one empty, letting them clatter to the ground. He raised his hands, bracing.

Eijiro frowned, "Your explosions aren't enough to hurt me Katsuki. This is pointless."

"Shut! Up! And! Die!" Bakugou exploded forward. The next minuet the air around Eijiro became a nova of firework blasts and screaming. Each explosion more shaky than the last, layering against his skin ineffectively. Sweat dripped from Bakugou's chin, his muscles trembled. He slipped, catching himself on Eijiro's shoulder and shredding his gloves and palm on the redhead's razor sharp skin.

Eijiro tutted, trying to grasp the blond's palm to look at it but Bakugou just released another explosion, trying to shake off his grasp and adding the smell of burnt flesh to the air.

That was the last straw.

"Enough!" roared Eijiro, clasping Katsuki firmly by his hand and turning him away. He trapped the blond against him, back to chest, arm like a steal band. Holding the raging teenager just slightly off the ground. Katsuki struggled, layering Eijiro's arm with explosions which petered off into small popping sparks as his sweat ran dry. Eijiro endured, frowning all the harder when the blond continued to try and claw at his skin, kicking back at him and trowing his head back, snarling and screeching like an animal.

Eijiro squeezed slightly, just enough to wind the boy. Waiting for him to tire himself out. Eventually, Bakugou's kicking slowed and stopped, his palms fell silent and his cursing turned into gasping breaths. He hung limp in Eijiro's arms, head bowed, hair covering his eyes. Defeated.

Eijiro slowly unhardened, layer by layer. Placing the boy back on his feet but not releasing his hold entirely, turning the restraint into an awkward hug.

"Enough Katsuki" he said much more gently. "You've done enough."

"I told you to stop fucking calling me that" Bakugou wheezed.

Eijiro paused, swallowing with a dry mouth. Hurt welling within him.

He pushed it down. Reminding himself that this wasn't his Katsuki, wasn't his husband. That this was an altogether different reality. A different Bakugou. Eijiro should respect his wishes, no matter the pain in his heart.

"Bakugou" said Eijiro dryly, no knowing how to continue. He released his hold, Bakugou stumbling away from him, turning to keep Eijiro in his sights. But his shoulders were slumped, his knees trembling. The blond gnawed his lip savagely, frustration written plain across his face.

Eijiro wanted to reach out, to offer comfort, but Bakugou had made it clear he didn't have the right. That was for a different Kirishima. Eijiro ran a hand through his hair, feeling emotionally wrung out and still a bit off from his reality shift. He hadn't expected confronting everyone's younger selves to drain him so much. The emotional turmoil sucking the energy from him far better than a spar ever could.

Maybe he really was getting old.

—

"So, now that you have finished embarrassing me with that rather abysmal showing, does anyone want to comment on what you did wrong?" asked Aizawa, once everyone had caught their breath. Eijiro shot a look towards Bakugou, expecting some sort of reaction to such a derisive comment, but the blond remained in surly silence. Head still bowed, but fists clenched tightly.

"We picked a fight with a rock" replied Kaminari, shoulders dropped. The electric user had been even worse than useless in the fight.

"We did not coordinate our attacks" said Yaoyorozu slowly. Her brow was still crinkled but otherwise she seemed to have regained her composure, taking her loss as a learning opportunity rather than being depressed about it like the rest of the students. There had been a reason she made it to number one before the rest of them.

"That's one way of looking at it" cut in Aizawa. "Not one of you attempted to work in combination. You had twenty minuets in which to plan a strategy and none of you took it."

There was silence, broken only by the sound of several students shuffling as they stared resolutely at their feet. Embarrassed and disappointed in equal measure.

All Might coughed, catching everyones attention. "Now, now. It was still an impressive display. Perhaps Kirishima could give us his impression of everyones abilities? As he knows what you will be capable of in the future."

Eijiro rolled his shoulders, twenty pairs of expectant eyes focusing on him. How to put this?

"Like Aizawa said, you need to work on your coordination. There were twenty of you and one of me, if you had simply focused your attacks, instead of coming at me one at a time, I would have had a much harder time." Eijiro ran a hand through his hair, blowing out a breath. He had never done well with giving criticism, Katsuki said it was why his interns liked him so much. "But more than that, you need to stop being so straightforward. And think! Actually look and think about your next move before attacking."

Several students blinked at him, confused. Ida's hand shot into the air.

"Sir, could you give an example?"

"Sure," Eijiro cut his gaze across the class, crossing his arms as he got his thoughts in order.

"Well, lets go through the fight shall we. Bakugou, you howitzered me at the beginning. It was an extremely powerful opening move that would have overwhelmed most people."

Bakugou smirked, lifting his chin just slightly.

"It was also completely pointless," finished Eijiro. Bakugou's smirk dropped, fury returning to those red eyes.

"You know my quirk," continued Eijiro. "You know what I'm capable of. Even at your age, I should be able to withstand that attack. A penetrating explosion, like AP shot, would have been much more appropriate, and you should know that. The only thing your howitzer did was almost harm you teammates, keep everyone else from attacking, and tire yourself out."

Bakugou scrunched his face, teeth grinding. Eijiro could tell he wanted to yell, to defend himself, but in the face of logic there was nothing to say. Denying it would just make Bakugou look even more childish.

Eijiro moved on, locking eyes with Midoriya, who gulped. "Then we have Midoriya, who continued to use the same attack against me again and again. Despite me having already defended against it easily the first time. What were you thinking? That as long as you tried to hit me harder it would work? You saw me tank Bakugou's explosions and Yaoyorozu's cannons. What made you think your punches would be any different?"

"I-er-I" Midoriya stammered, trembling eyes seeking All Might as he fiddled with his gloves.

Eijiro frowned at him. "Your quirk might be powerful Midoriya," Eijiro said solemnly, capturing the boys attention once more. "It might even be one of the most powerful quirks out there. But it's hardly the only powerful quirk in the world, and it certainly doesn't make you invulnerable. Simply putting in more effort and trying to hit someone harder won't cut it. You need to think! You need to assess! I know that your good at analyzing quirks, so why you limit yourself to only trying to punch people in the face I don't know."

"And the same goes for you Yaoyorozu." The ponytail girl straightened, suddenly being singled out. "You saw me take Bakugou's attack. What made you think I couldn't withstand a cannon? Your quirk is one of the most diverse out there, limited only by your own smarts and creativity. So be creative!

"Todoroki, same again. All you did was try to overwhelm me with power. I thought for a moment you had decided to use your fire as a smoke screen while you coordinated an attack, but instead you simply came at me yourself. Despite knowing that my quirk makes me resistant to temperature extremes.

"Kaminari, Oujiro, Shoji, Sato - I admit, I'm probably one of the worst match ups for you guys in a fight. In a real life situation I hope the four of you would have the smarts to stall for time until someone capable of fighting me came along. But each and everyone one of you came at me head on. I get you want to show off your abilities, but you would have been better use to everyone if you simply stood back and strategised. I cannot emphasize enough just how much easier a take down is if there is someone coordinating everything. In my time hero agencies fight over the best spotters for raids, they're that important.

"All of you," Eijiro looked around, making sure to catch the eyes of every student and really drive his point home. He hoped they understood where he was coming from. He knew just what amazing things they could do in the future, just how powerful they could become, but he also knew that continuing as they were right now they wouldn't be living up to their potential. And that was just about the worst thing Eijiro could think of.

"You can't all just rely on overpowering your opponents. Sometimes villains are simply more powerful. Or sometimes throwing your quirks around will just cause more damage than the villain itself. Collateral damage is a fact of life, but you should always be aware that it could be people's homes and livelihoods your destroying. You need to be more creative and less straight forward with your attacks." He ran a hand through his hair again, blowing out a breath, shoulders dropping slightly as he looked out over twenty downtrodden faces.

"You can't always rely on power, is what I'm getting at. Be imaginative, work together. If you do, you'll go a lot further as heroes than simply having a powerful quirk would allow."

No one said a word, contemplating in silence.

Aizawa clapped his hands, drawing everyones attention. "Well put," he said dryly, driving the point home. "First year at UA focuses mostly on conditioning your body and strengthening your quirks to be combat ready. In second year we will be focusing more on creative usage and situational awareness, but it never hurts to start early. So I want all of you to write a single page report on what you could have done differently during that fight, to be handed in Monday. You may collaborate on it if you like. Dismissed."

There was a collective slump at the mention of homework. Kaminari actually whining in distress. The kids headed for the locker rooms, eager to be out of their sweaty battle gear. Leaving Eijiro behind with the teachers.

"Don't make such a long face," said Aizawa, catching Eijiro's eye. "They'll bounce back."

"You don't think I was to hard on them?"

"No. If you hadn't said it I would have. Besides, I wanted them cut down to size and this certainly did it."

Eijiro sighed, trying to take his old teachers words to heart. "If you say so."

"I take it you've never considered teaching at UA Kirishima?" asked All Might in a much more joyful tone.

"Ha, no. I do my best just showing the interns the ropes. Katsu says if I ever taught a class they would walk right over me."

"Does Bakugou teach then?" asked Aizawa.

"He helps with combat training at UA. Kind of got roped into it by you actually. Something about a bet? I don't remember. It's been good for him though. We both don't patrol as much as we used to and I know Katsu gets angsty if he doesn't get to blow something up once a day."

Eijiro smiled, shaking his head in fond exasperation. As entertaining as reality swapping was, he couldn't wait to be home.