Author's Note: Oooh boy, first crossover here we come! (technically second but the first one was just a one-shot and quite silly– not that this one isn't, mind you, but you get the point).

The start is a bit lighthearted but there will be quite a bit of angst on naruto's part slowly because yk, I can't write that guy without his tragic backstories I'm sorry.

Anyway, hope you like the start! Read on!

Izuku strikes out his last sentence. It sounds too uptight to go into his internship application letter. He needs to find that perfect mix of formal amiability without sounding like he walks around flaunting a rod shoved up his ass.

He sighs, rubbing a hand down his face. Last week had been one hell of ride–what with the spontaneous villain takedown and subsequent practical exams. He's more than a bit exhausted but these letters need to be drafted and sent before midnight.

"Oye Deku!"

Izuku groans, blinking tiredly at Bakugo's incoming figure. Next to him, Ochako straightens up out of reflex.

"Yes?"

Bakugo places his hands on the table with force, leaning in as he always does. Izuku guesses it's some kind of intimidation tactic but he's too tired to feel wariness of any kind.

"You're applying to Endeavour's agency," he says but it sounds like an accusation, like a terrible secret Izuku is trying to hide.

Izuku blinks, shifting his papers on the off-chance that Bakugo might decide he's too angry to adhere to dorm rules and set his hardwork on fire.

"Yes," he says cautiously. "So?"

"So?" Bakugo mocks. "So when the fuck were you gonna tell me, huh? I'm applying there too and I sure as hell don't wanna get stuck with your stupid ass for a whole month!"

Izuku feels a pain deep in his gut. It's dull and throbbing.

"I didn't know you wanted to know, Kacchan," he replies, rubbing his temples with an idle hand. "You could've asked me if you really were so curious."

"I wasn't curious," Bakugo snorts, flicking his gaze to an irate-looking Ochako, then back to him. His eyes shine with fury and frustration. "I just want you to stop following me everywhere goddammit!"

A searing hot sensation shoots up Izuku's spine and he opens his mouth to retort but no words come out. He grips the side of his body, then touches his back gingerly. It feels hot, too hot, and he shuts close his eyes as another wave of pain sends his shoulders and knees on fire.

"Hey, Izuku, are you alright?" Ochako prods at his arm carefully, worry bright in her voice.

Bakugo goes silent but Izuku is too wrapped up in thinking he's about to die to notice.

Then, like his skin is being pulled inwards, stretching across his bones enough to tear, nerves across his body flare up. It's a deeply uncomfortable feeling–as if he is imploding, as if he is collapsing in on himself. His nails dig into his forearms and he lets out a silent scream.

And then the pain, the fire, the ache, the burns–they all disappear abruptly, leaving him feeling oddly bereft. He takes in huge, sharp breaths, forcing his lungs to function and his body to adjust to a pain-free existence. He opens his eyes to harsh light and familiar red eyes staring at him.

"What the fuck, Deku?" Bakugo asks but he looks shaken up and bewildered.

"Hey guys?" Tsu calls while Ochako squeezes Izuku's arm in reassurance. "Who's this strange dude in our living room, ribbit?"

Flexing his fingers to get some feeling into them, Izuku follows his gaze to where Tsu's pointing. Ochako and Bakugo do the same and soon everybody seated around them goes deathly silent as they all stare at the young man dusting off the side of his sleeves, ruffled blond hair contrasting his brillaint blue eyes. He seems unaware of their presence as he groans and rubs his right elbow, squinting at the floor.

Izuku feels an odd prickling on his neck and he stands up. The familiar tingle of One for All is trigger-ready under his skin and he's one wrong move away from pouncing on the stranger and punching his guts out. Iida meets his eyes, a silent understanding passing between the two: no matter what, they'll protect their friends.

Bakugo stumbles to his side and he feels the light heat wafting upto his face. He is accustomed to it, knows that it means a blast is incoming.

The stranger shakes his head, swiping off the haphazard strands of hair from his head. Muttering to himself, he looks up.

Warm blue eyes hold confusion as they survey the couches and tables all across the room before they trace over Izuku and his friends' faces. He frowns at them, back ram-rod straight, a hand slipping into his pocket. Izuku can see a fist forming inside, knuckles peeking out and he knows the guy is gripping a weapon of some sort.

"Who are you?" Iida steps forth and questions sternly. "Who gave you permission to enter our dorm?"

The man stares at him for a moment and says, "Naruto. I'm Naruto. Who are you?"

Izuku nudges Iida's shoulder, stopping him from responding.

"We won't tell you anything until you show us your ID and the pass issued by Nedzu or Aizawa-sensei that permits you to enter this building. Otherwise, you are trespassing."

The man–Naruto–looks at him and he feels the weight of his gaze, the casual scrutiny.

"Yes," Ochako chimes in, a waver in her voice. Izuku knows how terrifying this must be for her and everyone else. After all, the league of villains has never held back from infiltrating UA and surprise-attacking them before. "Show us."

Naruto's face softens visibly and he tries for a smile. "I don't have anything to show," he shrugs. "I don't know how the fuck I got here–" he slowly approaches the nearest couch, clearly telegraphing his moments, both hands held in front of him, empty. "–I was just... I was at the cemetery and then poof boom gahhh I'm here? How does that work? Oh! What is that black glass thing over there? Looks fancy."

He sits down, movements fluid and relaxed. It strikes Izuku as weird that this Naruto person is able to act this way despite knowing just how tense everyone in the room is.

"That's a TV, dumbfuck," Bakugo replies, scoffing at Naruto who is eyeing the appliance like it's the single most peculiar thing he has ever laid his eyes on. "And it's not fancy. Just a trashy model none of us even use."

"TV," Naruto echoes. Izuku can tell he's at least twenty but the genuine wonder on his face would not look out of place for a kid discovering video games for the first time. "What's it do?"

"What do you mean what's it do?" Bakugo spits back. "Are you playing with us? Or are you some nomad weirdo who swore off technology or something?"

Naruto hums and looks at him. "Nice sandals," he says.

"They're flip-flops, you idiot!"

"Got it, floppy."

"What did you just call me?"

"Floppy?"

"That is not my name!"

"Well, then, what is it?"

"Ha! As if I'll fall for your trick blondie! I'm not telling you my name!"

"Okay. Fine by me," Naruto snorts. "By the way, you're a blondie, too, if you hadn't noticed."

Bakugo is at his wit's end. Any moment now, Izuku knows he will charge at Naruto and a fight none of them need will ensue in full-force. He carefully moves his body so he's in front of Bakugo. If a brawl is going to break free, he at least wants a headstart at trying to prevent it.

"Hey, guys, let's calm down, alright?" Eijiro attempts to placate. Denki nods his head in agreement, shooting a terrified look at Bakugo's enraged form and the stranger darting his gaze from one object to the next, as if every piece of mundanity holds something inherently interesting in itself.

The phone in Izuku's pocket vibrates but he ignores it in favour of being vigilant.

"Calm down?" Bakugo grits, the same fire that had once terrorized Izuku forming in his eyes. He hates seeing it there, hates being reminded of how awful things once were and how no amount of burying it can erase those memories from his mind. He bites his lip, fists his hands and firms his stance.

"This dumbass can't just waltz in here and expect to not get his ass kicked!" he hisses at Eijiro who nods his head patiently at him.

"Yes," he says, "but we don't even know if he is a threat, bro! Maybe we should just wait till–"

The main door flies open just as the elevator behind them pings. Aizawa-sensei strolls through while Shoto joins them.

"You called him?" Izuku whispers to Shoto, a profound relief flooding him. Not enough to make him untense, but enough to take his eyes off Bakugo.

Shoto nods, quirking his lips. "I heard what was going on from the first floor's railing."

Izuku returns his half-smile with a sincere one of his own. "Thanks."

They turn their attention towards Aizawa just in time to see their teacher's scarf floating mid-air, wrapped loosely around a throw pillow. Naruto isn't on the couch anymore but just a few steps behind their surprised sensei.

"Who are you?" Aizawa asks sharply, turning around. His characteristically bored eyes are blunt stones that assess Naruto's every movement, every twitch of his muscle.

"Naruto," the blond says, huffing. "Will you stop hovering around your– your weird bandage? I'm not a threat."

"I won't and whether or not you are a threat is something I will decide," Aizawa replies, darting his gaze towards them, nodding to himself and turning back to Naruto. "How did you teleport? Is that your quirk?"

"Teleport?" Naruto rubs at his elbow again. Izuku figures the man has some sort of injury there. "It was the substitution jutsu. But, what's a quirk?"

Aizawa's lips thin out, "Doesn't matter. How did you get in here? You're trespassing."

"I am not tres-whatever-ing," Naruto says, blowing a breath and swiping at his hair again, smoothing it back. "I don't know how I got here, alright? One second I was in Konoha and next, I fall onto this weird rug, landing badly on my arm with these kids staring at me like I'm the devil reincarnate. What is this place anyway? And will someone please tell me what this TV thing does already?"

"I am not in the mood for your stories and lies," Aizawa says and there is a clear warning in his tone. Izuku tenses again, prepared to assist his teacher if need arises.

"I am not lying," Naruto states seriously. It's the first time they've glimpsed such an intense expression on his face.

"But you are committing a crime," Aizawa says. "So cut the bullshit and empty your pockets. I'm going to take you to the authorities. Let's see how much of what you say holds true then."

"Authorities?" Naruto cocks his head to his side. "Are you a shinobi? From what village?"

"This is no village," Aizawa replies. "And by authorities, I mean the police."

Naruto's face tinges with curiosity again. "Didn't know any village had a secondary law enforcing unit after what happened with the Uchihas."

"What?" Aizawa says flatly.

Naruto shakes his head, looks right at Bakugo. "Hey, floppy, what's this TV do?"

Izuku glances at Bakugo from the corner of his eye. The boy doesn't look too happy at being addressed.

"Go fuck yourself," he replies.

"You're their teacher?" Naruto asks Aizawa, turning away from them once more. "You should teach that one some manners. He's so rude, y'know?"

"I kno–" Aizawa coughs. "Empty your pockets."

"No, thanks," Naruto says. "I'm not staying."

Aizawa's eyes blaze red and his scarf shoots forth just as the man finishes his sentence. But before it can loop around him, Naruto is already gone, the remnants of a cool breeze and tendrils of smoke the only indication that he'd been there.

"Todoroki, Midoriya, Bakugo, Iida!" Aizawa calls, looking as exasperated as he always does but there's something rigid in his posture, something unsettled in eyes. "With me to Nedzu's office–now!"

Author's Note: ...That's it for the chap one! Hope you enjoyed it. As always, any feedback is welcome!

Thank you so much for reading and hope you have a wonderful day ahead!!