This is my first fanfic for this fandom, so I really hope I managed to keep them in character. Also... this was supposed to be a pure fluff one-shot because I need fluff after everything that has happened... but somehow it turned kinda brooding on the way (that's my fault), and long, really long... so I really don't know what this is any more or exactly where it's going to go, I just know I had to split it into chapters and that the first part needed to be posted in hope of it not being a total mess. The thing is, I've never done a fanfic with chapters, and my objective for the one-shots I've written is always very clear... but this one story... it seems to have taken a life of its own...

Anyway, this is probably set around the time Izuku returns from training with Gran Torino. Manga readers may catch some very subtle stuff, but no worries, I especially wanted to write this one spoiler-free for people that aren't reading the manga.

All Sick

It had been a long two weeks of tests at UA, and it had practically been the same amount of time since Izuku had last talked with his favorite hero and mentor, so when the exams finally ended and they went back to their normal schedule, he couldn't be more excited when the time for their Foundational Hero Studies class arrived. Yet, when the door opened, it wasn't All Might announcing his entrance in the awkward ways he enjoyed to do so, but Aizawa-sensei with an irritated expression.

"So, it seems like All Might won't be able to join us for his class today, so you can use these three hours of class to study," said the hero.

"What? But… didn't he come back from his special mission yesterday?" asked Izuku with disappointment dyeing his voice before he could stop himself.

Izuku's slight pout made Uraraka smile. She had made a hobby of watching those two interacting. All Might always had a smile for everyone, but she was sure that his smile always looked a little brighter when Izuku was around, and naturally, everyone knew that Izuku always beamed whenever he saw his all-time hero, so she couldn't help to find it rather endearing when she saw them interacting or talking about each other.

"Well…" started Aizawa, not even surprised anymore that his student would ask about All Might and that he'd know he was supposed to be back by now "Apparently, the number one hero called in sick" continued Eraserhead letting his annoyance show in his red-rimmed eyes. "As reckless as always, I'm sure" he murmured before getting into his sleeping bag and going to sleep in a corner.

Almost unconsciously, Izuku took out his phone with a frown and sent a quick get well message to his mentor before taking out his notes to study.

The rest of the day continued uneventfully with Izuku looking now and then at his phone, message unseen. Finally, by the end of the school day, he took out his phone once again and looked at the messages history where he read his most recent text:

[Aizawa sensei told us you called in sick, I hope it's nothing serious. Please, take care of yourself, All Might.]

It was then when he noticed the date of the previous messages, and realized guiltily, that he hadn't sent a single message to All Might since his exams had started. It's not like they communicated all the time through messages, most of the times All Might would simply send him a message to meet him somewhere or call him directly if he wanted to tell him something important, but when they were apart, if Izuku was honest, he probably bothered the pro hero more than he should. He'd find any excuse to write to him, but All Might would always answer good-naturedly, sometimes in a couple of minutes, sometimes after an hour or two, sometimes even surprising Izuku with a silly joke or a kind reminder to be careful. And All Might, well, sometimes he'd write to ask how his studies where going, to share training ideas, there had even been a couple of times where he had even indulged Izuku's fanboy side and asked him if he had seen the latest fight between a notorious hero and a villain. But for the past week… well, it's not like Izuku hadn't thought about messaging him the first couple of nights, for goodness sake, the boy couldn't be more ecstatic to be All Might's pupil and to actually have his phone number, but he knew All Might had been called for a special rescue mission in Antarctica, so he felt guilty to bother the professional hero with nonsense, and then, he had been so busy studying with everyone, that he could only think about crawling to bed at the end of the day.

He looked at his last message again, still not seen.

It's not like All Might to take this long in answering. Is he alright?

All Might had told him before leaving about his mission. A group of explorers had been trapped inside a cave under the snow by a band of villains that apparently shared akin quirks that involved ice. The rescue mission required a quirk that could counter ice efficiently and a lot of strength, speed, precision and experience to take the explorers out, so naturally, the best choices had been none other than the number one, and the number two heroes.

Unsurprisingly though, Izuku had managed to get the time to see him and Endeavor in the news daily, hence why he knew All Might should be back by now. He tried to remember if he had seen the pro hero show any signs of sickness or injuries, but as usual, All Might would never allow himself to show any weakness in front of the media, after all, the symbol of peace could not be daunted by evil, he should always stand firm and laugh any pain or fear off.

His number one fan sighed.

What if something happened to him? What if he overextended his muscle form and hurt himself? Should I go check? He could be in trouble. The teachers at UA seemed unbothered, so it's probably nothing serious, but… No, this could definitely be an emergency!

He stopped his train of thought when he realized he had reached instinctively to the key he kept hidden in the deepest corner of his bag pack. He looked at the keychain with a fond smile, it was a ridiculous old bunny with ears that looked suspiciously similar to the signature bangs of a certain hero.

All Might gave you a copy of his apartment keys for only strict emergencies. The boy reprimanded himself.

He knew the number one hero was used to having a lot of attention and appeared very comfortable in front of the cameras, but in truth, he was fiercely protective of his privacy, and apart from a few close friends, he appeared to keep to himself most of the time, probably another inevitable consequence of being the symbol of peace. It's not like he wasn't social, quite the contrary, he always knew how to lighten up a room and how to make everyone around him smile with his antics, but he had probably grown accustomed to keeping people at a safe distance to protect them, and then, to protect his secret true form.

What are you thinking, Izuku? He's probably just resting. Besides, it's not like he doesn't have better things to do than answering your messages all the time. It's good enough that he gave you his trust and One for All, are you seriously expecting him to answer to your every message? It's not like he's your da…

This time he physically stopped on his track when he realized where his muttering was going, a warm rush rapidly invading his cheeks up to his ears. All Might had always been his absolute hero, but after he had met him… well, he had become even more than that, in fact, so much more than that. Izuku knew for a fact that he was kind and supportive with every student, after all, everybody loved him, but he couldn't lie either and deny that the emaciated hero had gone out of his way to support him. He tried to train with him as often as possible, he was always considerate of his feelings, and he often stayed a little longer after the training was over to simply spend time with him. For goodness sake, he even smiled at his endless chattering most of the times, unless he was trying to make a point, then he'd get exasperated at Izuku's nonsense and silence him with a not-so-strong hit in the head. Probably the pro hero would scoff and call him a fanboy if he knew how deeply Izuku regarded him, but he couldn't help to see him like a father figure after everything he had done and kept doing for him. He was no longer just the number one hero that always smiled fearlessly through the screen, not even the clumsy but caring teacher of UA, but the emaciated hero that kept on smiling despite all his burdens and his fears, and the supportive and warm mentor that had believed in him and that was always there for him.

"Midoriya? What were you muttering about?" Kaminari's voice snapped him back to reality.

"Yes, you seemed to be a little out of sorts today. Are you okay?" Iida came close to him and took a stern look at Izuku's distracted expression.

"Anyway, we're going to get some ice cream to celebrate the end of the exams, wanna come?" Suggested Kaminari with a big smile, but getting nothing but a blank stare back from Izuku.

"…Deku?" asked Uraraka getting close to him, close enough to make him snap back out and instantly blush apple red.

"Eh… s-sorry, I-I need to go somewhere!" he mumbled before waving goodbye, his legs moving before he realized he was running in the direction of All Might's apartment.

Meddling when you don't need to is the essence of being a hero.

"All Might, I hope you don't get mad… but I just want to make sure you're alright" said the boy to himself as he increased his speed.

He didn't like to dwell too much on it, because his heart ached a little every time he did, but it was easy to see the emaciated hero was awful at taking care of himself. There could be no harm in just checking on him, right?

Izuku had only seen his apartment once, but he had engraved every single detail of it in his mind. At first, it had surprised him, it was in a rather old and shabby building compared to the magnificence of the Might Tower, but then, he had smiled understandingly, proudly. Many people probably assumed that All Might would live in wealth and pretentiousness, but he knew better, the hero wasn't interested in those kinds of things, very few people knew this, but his most avid fans knew that almost all the money his agency received was destined to help different organizations.

He knocked softly.

…Nothing.

He knocked again.

….Nothing.

He strained his ears. Still nothing. Should he use his key? It wasn't like he could call his name and attract unwanted attention. He swallowed guilt and excitement at the same time unsure if he should be allowed to be there, turned the key and pushed his way in.

The room was completely dark, he remembered that near the entrance was a simple coffee table and a couch, at the side was a small kitchen with a kotatsu and at the back were his room and a small bathroom. In the darkness, he could spot a shadow laying in the couch, he realized it had to be the number one hero, as he could hear someone breathing. His heart clenched when he realized that the breathing was nothing but an unsteady wheezing.

"…All Might?" he whispered.

There was no answer.

Izuku waited until his eyes grew accustomed to the dark. He could see the table was filled with used paper tissues, he should have guessed, he had seen All Might come in and out of the cave carrying drenched people with nothing but his hero suit. He had probably been soaked wet the entire time as well. He squinted his eyes, All Might's messy hair stuck out of a huge quilt. The hero's breathing was painfully straining, but it was regular enough to tell Izuku he was indeed, asleep.

He tiptoed to the couch. Although the quilt covered most of All Might's head, half of it had dropped leaving the rest of his body uncovered. The boy noticed his mentor was shaking of cold, smiled warmly, kneeled down and very slowly started lifting the quilt to cover the hero. But the moment he had touched the quilt, he felt a tug, a dash of wind, and then, when he finally managed to catch on what was happening, he saw the hero had jumped out of his skin to stand on the couch, just to slip with the quilt and crash against the back pillows making the couch fall back while a perfect fountain of blood came out of his mouth as he fell along with the couch.

If the boy hadn't been as worried and mortified as he was, he would have burst into laughter, because he could swear he had just heard All Might make a cat-like hiss before jumping out of his quilt.

For a whole minute, there was no other sound than All Might's fast wheezing behind the couch until he heard the familiar voice "…Young… Midoriya?" It seemed like it had taken a while for the hero to digest everything that had happened too, which was in itself worrying, considering how trained his senses usually were.

Izuku practically jumped from the floor, turned the lights on and ran to kneel by his mentor, who was still on the floor, tangled in his own quilt.

"YES! All Might, are you okay!? I'm so s-sorry for entering without permission, I didn't mean to startle you. No, I'm sorry for coming without asking you first, I know you gave me your key for emergencies only, and I guess I have no business coming, but I was kinda worried because you didn't answer to my message and I thought I could do achickensoupforyoubecausemymomalwaysdoesthatformeanditmakesmefeelbetterand-" he started practically screaming with a high pitched voice that soon turned into his familiar endless muttering.

"My goodness, enough already!" All Might interrupted his reverie resting a hand on his forehead and closing his eyes "Your endless nonsense's not helping my headache…" rasped the number one hero lowering his legs from the couch carefully and sitting on the floor right before a fit of coughs filled his chin and fist with blood.

Izuku's stomach churned, actually, now that he could see his hero in the light, All Might looked awful, his eyes were dull and teary, his nose slightly red, and he was looking paper white pale. Sure, he was used to his paleness and to the fact that during the evenings, after having coughed blood who knows how many times, he'd look a little paler, but this was too pale, even for him, and if he looked carefully, he even thought that his lips had a bluish hue to them.

"I'm sorry…" Izuku felt his throat tightening. He only wanted to be there for All Might as he was there for him, and he looked so ill it broke his heart, but he had only managed to disturb his sleep and to annoy him with his senseless chattering.

"Please, don't ever wake me up like that again…- started All Might lifting a hand so Izuku would allow him to continue "…but I am grateful that you came to check in on me, my boy" he said with a soft chuckle rumbling in his chest and a smile climbing to his eyes.

"Wha-?" Izuku gasped and averted his gaze to the floor when he realized his face was as red as a tomato "It's the least I could do for you, All Might!" he muttered embarrassed, voice filled with earnestness.

"Well… it's more than I could ever ask for…" said the hero in a soft voice. Had Izuku just imagined that sudden, devouring feeling of deep lonesomeness in his tone of voice?

"…All Might?" The boy couldn't stop the deep emotion in his own voice as a sudden rush of unbundled sorrow invaded him, All Might's sorrow. The pro hero always brushed his problems aside and kept on smiling to life, so to suddenly realize he could harbor such loneliness, to think how lonely it should be to be at the top, carrying all the burden by himself, supporting everyone, but everyone assuming he didn't need their support, instantly crushed Izuku's heart for the hero he loved so much.

The symbol of peace was aware by now of the meaning behind each tone of voice his boy - young Midoriya – he corrected in his mind – had, so when he heard such an unfathomable feeling in it, he instinctively looked directly at his eyes, they were round and filled with raw understanding, it took him aback, and it was then when he realized what he had said, or rather, the way he had said it. Of course the boy would look like that now, Midoriya was a machine of empathy, and they spent so much time together, it was a matter of time before he'd tune in to his feelings as well, especially when his mind felt so sluggish.

Pathetic, I am so pathetic. He mentally kicked himself. How can I feel so wretched because of a simple cold!? Some hero I am, getting all sentimental over the domesticity of a sick visit!

"Don't worry, my boy." he started with a crooked smile. "Why though? Because I am all right" he said with a raspy voice while shakily standing up and lifting a fist to add power to the pose "Or rather, I am All Migh-" but before he could finish, his eyes rolled to the back of his head and his body went limp.

Izuku gasped, unleashed One for All full cowl in a matter of seconds, and stood in time to catch the unconscious hero on his shoulders. He was as light as a feather, but he was still a lot taller than him, so the boy carried him awkwardly.

"…A-All Might!?" asked young Izuku with a shaking voice. There was no answer, just the feeling of All Might's body shaking with chills and the sound of his withered respiratory system trying to grasp for air. "All Might!?" He asked more urgently already feeling tears forming in his eyes.

He reached for one of his arms to shake him, only to realize with dismay that his mentor's skin was ice cold. There wasn't any warmth emanating from the emaciated hero's body. Didn't he have a cold? Wasn't he supposed to be burning up? This had to be bad, really bad…

"ALL MIGHT!"

A few authors notes:

-There's a chapter in BNHA SMASH! where the kids help All Might move and they see he used to have a cozy kotatsu, BNHA SMASH is not exactly canon, they are mostly silly or weird puns, but I found that particular detail sweet, so I'll assume he likes them.

-There's no complex plot in here, so his skin being cold is not due to any weird quirk, it's just a possible symptom of what he's got.

Again... hope you liked the first chapter of whatever this is, I have most of chapter two done and have no idea how long this is going to be, probably it will depend on its own momentum and if there are readers interested in more. If you feel like it, I'd love to hear what you think!