Summary: Tony taught himself to play the piano when he was six and now he can hear the music in his mind. He's never played the piano for anyone but himself before, but Loki changes that by intruding.

Turns out Loki loves music and the two bond.

Pepper is oblivious until the last second.

Warnings: AU, Slight Avengers/Iron Man Crossover, Hint of Slash, Music, Madness, One-Shot, Mentions of Torture, Fluff, Tony has a Secret, Pianist!Tony, Stream of Consciousness, Out of Character, Hearing Music, Friendship, Fluff, Loki Feels, Tony Feels

Pairings: Hinted Loki/Tony

Grand Piano

Written By: -Ciel Leon-

Tony Stark has a secret.

It's not like what everyone who knows him would expect- it's not blueprints of dangerous weapons or new technology of any sort really.

No one, not even Pepper knows that the piano that sits in the foyer isn't just for decoration.

He keeps it well tuned, and only plays it when he knows there is no one but JARVIS around to hear, and it isn't because he's shy- hell, anyone who'd ever meet Tony Stark would tell you that of all things Tony is not shy.

Tony just can't seem to appreciate the music he makes when anyone is listening.

He had started teaching himself to play when he was six, entranced by the music the woman that took care of him listened to- a woman he can't even remember- but it doesn't matter where the idea to learn came from, all that mattered was that Tony wanted to master the piano. He wanted to feel the smooth keys underneath his fingers and the reverberation of each note he could possibly make.

It was a yearning that Tony carefully let slip into the background of his very being because his music was one of only two things his mind could retreat to when stressed, and his music wasn't something anyone had to hear, notice, or criticize.

When Tony couldn't focus on schematics or blueprints, not to mention endless wires and metal his whole mind would shift focus and everything came to him in… noise.

In noise and notes and colors and emotions an endless cacophony of pure sound that would reverberate in his ears in a way Tony couldn't and never would even desire to ignore.

When he was eighteen and finally out of his father's grasp, he used his own, hard earned money to do three things: buy himself a warehouse, a new piano, and bundles of sheet paper because his music was the one thing that could always soothe him.

When Afghanistan happened, Tony went half-mad.

He heard music everywhere playing all sorts of rhythms, beats, and melodies and then the other half of his mind worked hurriedly to come up with something that could save both his and Yinsen's lives.

During the building process, his mind played notes of deep and dark undertones which formed to hold a steady rhythm even as they repeated themselves with only a rise or fall in pitch to indicate any form of change- any high or low point in his work.

When the escape came, the music in Tony's mind was rushed and loud, screaming for attention even as it throbbed with an undercurrent of horror and sadness with a slight hint towards triumph and then, soul- lifting freedom.

The music didn't stop playing for him when he returned to Malibu.

Didn't stop when he had that press conference to tell the world the manufacturing of weapons by Stark Industries was over. Finished. Caput.

And the music made Tony feel lighter than he had in years even though he had no time to concentrate on it or to write it down, it was his constant company and it lifted and fell just as smoothly with his true emotions as JARVIS's voice welcoming Tony home.

His music was just as much part of him as his engineering was.

When he could, Tony went to the Warehouse he had kept his piano in since the first day he'd bought it and played.

He spent days there, just absorbing the way the music sounded out loud instead of confined to his mind and he wrote every note and bridge down with the motions built from years of practice and in times like these, he even tended to ignore the calls he received no matter who it was on the opposite end of the connection.

Sometimes, when he came back to the real world from these trips into his music, Pepper or

Rhodey and occasionally Obadiah would ask 'What the hell have you been doing? Where the hell have you been?' And Tony will just smile, relaxed, sometimes even make a sarcastic comment, but generally, he won't answer.

With the realization of Obadiah's' betrayal, when he is weakly dragging himself to his own lab, the music within his mind is made of a jumbled mess of high pitched and deep baritone as well fast sections overlapping slow notes- and Tony distantly wonders if this is what dying is supposed to sound like, or if this is just the way dying sounds for him.

Fighting with Obadiah who is in that monstrous, clunky, outdated version of Tony's own Iron Man suit causes the notes within his mind to deepen, repeat and constantly pick up pace and there are no pauses, just an endless repeating melody rising in pitch until it reaches a crescendo with the surge of energy that comes from the Stark Industries Arc Reactor.

Tony nearly dies for a second time as the reactor within his own body- the one he made to replace the car battery within that infernal cave- sputters weekly and dies. This time the notes in his head are slow and deep arching slowly within the confines of his mind before going out with a gradual decrescendo until the volume Tony 'hears' is only as loud as a whisper before everything dies out completely.

When he wakes, gasping for breath the music is loud and pounding on the walls of his mind with a single-minded determination.

The determination to live- to play his music one more time- to build something one more time- to breathe one more time.

Tony Stark lives, though slightly worse for wear, and announces he is Iron Man to the world.

When Loki lands on Midgard, he isn't anywhere near the Tesseract.

The god is tired, furious, lost, and confused and nothing is making sense.

It's dark wherever he is, there are bulky buildings surrounding him on all sides and city lights seem far away.

Loki is about to teleport to where he can vaguely sense the Tesseracts' energy- except he can hear something.

The god blinks and calmly surveys his surroundings; there is no one in sight.

The longer he stands here, the more Loki hears and he can tell after a few minutes, that what he is hearing is music, a piano to be precise, and the melody he is hearing is like nothing he's ever heard before- it's fresh, alien, and holds a mix of content and sadness within the notes he hears and Loki is walking before he even realizes it.

He's following the sound, winding between buildings and relishing in the music he hears, until he finally reaches a door as the music reaches a crescendo that suddenly falls flat onto a single lone note that tappers off, and there is silence for a few seconds before the notes begin to fill the air once more.

It starts with that same ending note, piercing and brief which then repeats itself and is soon joined by several other keys flowing smoothly into one and then after moments of this winding melody Loki finds himself opening the door to the building and entering as the music suddenly, yet

somehow wonderfully seems to fall apart one note at a time until that last note ends it all as it pierces the air on its own once more, briefly this time, before there is silence.

Loki didn't realize he'd closed his eyes, but when he opens them, he takes in the sight of a man behind a smooth polished black grand piano that seems to have delicate engravings etched into its legs. The man is a mortal of course, probably in his late 20's early 30's, brunette, and slightly muscular, with brown eyes.

The mortal is focused on what seems to be a sheet of music perched upon the grand piano and Loki wonders if the man was merely playing a piece created by another mortal before he sees the man, who, Loki realizes, is holding a pen, reach towards the sheet and making several notations and the warehouse causes the sound of breathing and the scratching of pen against paper to echo.

It's only when the man behind the grand piano has released the pen that Loki makes his presence known.

"It's beautiful."

Tony blinks, the voice is musical too, and soft, it pleases his ears more-so than any other he's heard before.

He looks up to where the voice is coming from, slightly confused and yet curious and the sight that meets him worries him slightly as well.

It's obvious that his intruder isn't from anywhere around here- possibly not even from Earth despite the fact Tony knows such a thing shouldn't be possible. The other is wearing black leather mixed with green fabric which is all accented with the gold armor plating and the odd staff he's also carrying. The man has obsidian black hair and his eyes are a startling green, and from what Tony can see, his intruder also has fine bone structure if those cheek bones are any indication. However, this isn't what worries Tony, the man is clearly exhausted with rings of black underneath his eyes, he's pale- like he hasn't seen the sun in weeks and Tony can see the man's shoulders hunched slightly as if he's being weighed down by something.

Tony says nothing, just cocks his head to the left as he meets those green eyes.

And the intruder asks, "Will you play again?"

Tony hesitates.

It's his music, and he has never played for anyone before… but this man seems generally inquisitive, as well as eager, so Tony returns his gaze to the piano keys, glides his fingers over those white keys, closes his eyes, opens his mind to the world, and plays.

He's never played anything close to what's pouring into the air now, it's unique, and Tony knows that this one will never go on paper because it belongs to him just as much as it does the man that is the first to listen to him play.

When the music ends, and Tony comes back to reality, his intruder is gone, and Tony knows that the door never opened.

He was listening for it.

Tony closes his eyes for a moment sighs and stands before picking up his most recent written work and heading for the warehouse door.

It's when Tony is about a foot away from where the man was standing that he spots something set against the white tile of the warehouse floor.

He picks it up.

It's a slip of parchment, heavier than normal paper and slightly rougher, and when he turns it over, Tony spots the writing in green ink.

'Thank you for allowing me to hear you.'

Tony can't help the quirk of his lips before he slips the note into the folder holding his music sheets and leaving the piano behind.

Sometimes Loki comes back to the warehouse where the mortal played that beautiful piece of music for him and wonders what the man is doing, who he is, why he plays here instead of in his own home.

Loki's mind over flows with questions and he doesn't realize until several weeks after that isolated incident that he doesn't actually feel a draw to do anything Thanos has ordered him too.

After three weeks, Loki snaps the scepter in half and merges into Midgardian society.

He wonders if he will ever see the mortal that changed his whole perception of man-kind ever again.

Loki finds out who the pianist is three weeks and two days after his arrival.

He sees the mortal on the… television… in a shop window as he glides through the crowds on the streets of New York City.

Tony Stark. Billionaire, genius, playboy.

Loki can see through that fake smile the man is wearing.

Tony is feeling stressed and slightly harassed.

Pepper is unknowingly pushing Tony into a corner and Tony was already at breaking point, and it really hasn't been a good day.

He leaves, grabbing a pair of car keys as he storms his way down to the garage, ignoring Peppers yelling.

Tony uses the Key fob to figure out which pair of car keys he has before slipping into the vehicle and tearing out of the garage.

His phone goes off a few moments later and Tony tosses it into the back seat, turns on the radio and raises the volume.

The music in his head is desperate to be unleashed into open air.

When Tony reaches the warehouse he parks the car and bursts inside, heading directly to the piano where he throws himself onto the bench before carefully lifting the cover protecting the keys and throwing himself into the music, playing like a mad man.

The music is angry, unrelenting- no pauses, no slowing down- only a rise in pitch or longer note duration.

The music only calms hours later and Tony is sweating in exertion but his muscles are now relaxed and his once chaotic mind is somewhat calm.

He looks up and Green Eyes is there, quietly watching him with a pale hand resting on the piano.

The man looks better than he had when Tony had first seen him, no longer having bruises under his eyes and the skin is a slightly darker shade, and when he looks into those eyes Tony realizes he has not calmed just himself, but also his companion.

"Do you want to talk about it?"

Tony sighs and silently shakes his head before saying, "It won't help, I'll just get angry all over again." He runs a hand through his hair.

The other man hums noncommittally.

"Loki Odinson."

Tony blinks, smiles- genuinely, "Tony Stark."

Tony is intrigued by Loki.

They only see each other when Tony is at the warehouse and Loki occasionally intrudes, but Tony slowly realizes that he is growing calmer, the music isn't always harsh and pressing, he doesn't drink as often, he's coming up with new ideas (for both his music and his tech), he's not whoring himself out as much and Pepper is wondering what the hell is going on.

Tony finds himself retreating to the warehouse more often than ever, though he still spends a lot of time in his lab.

Playing is no longer just an outlet for emotional relief, now it is a hobby, and he loves it as much now as he used to when he started learning how to play.

One day, when Loki turns up, Tony eases the piece to its finish and asks Loki if he wants to learn.

Turns out a self-taught pianist can teach others just as well if not better than an actual teacher, that is, if your teacher is Tony Stark.

One day, they end up talking about their pasts.

Loki is hesitant before telling Tony he's not from Earth.

Tony just grins and says: "I figured that out a while ago."

Loki smirks and continues haltingly.

The god speaks of Asgard and its rivalry with Jotunheim.

About the war between the two realms and Odin Allfather who stole a Jötunn baby left to die upon the steps of a temple and the spell the man cast to keep the child's true form hidden.

He speaks a little of Thor, his brother, who he grew up with, loved, cherished, until the prince's shadow nearly suffocated Loki along with the man's pride and warmonger actions.

Loki talks of his subtle trickery, Thor's banishment, the way Loki was desperate for approval from Odin, even more-so upon the realization that he was a monster from the tales he was told as a child.

Tony knows he can't interrupt, can't push either, because if he interrupts Loki won't be able to speak of any of this for a long time. Tony knows it's a raw wound- still fresh and bleeding, slow to heal and will scar- so he lets Loki talk and resolves to tell Loki his own past when the god is ready.

Loki's voice is low as he speaks of his coronation, the invasion and subsequent killing of Laufey Loki's real father-the betrayal of the Warriors Three, Thor's return, the battle on the Rainbow Bridge, and then Odins disapproval as Loki hangs suspended above space with only Thor to keep him from falling- Loki letting go.

At this point Tony stands and carefully pulls the god into an embrace knowing, at least slightly, the despair Loki must have felt. For a few moments, Tony thinks Loki's tale is over, but the god continues, voice raspy and body shaking within Tony's grasp and Tony is worried beyond belief because he knows Loki broke when he fell, but the fact he is continuing to talk tells Tony that Loki has actually been shattered and is only now slowly pulling himself together. Knows that he is the only person alive to have heard Loki's story.

Loki quivers as he speaks of the torture Thanos forced upon him until Loki wanted only to escape and told him of the Tesseract, an object of great cosmic energy that could open gateways and power virtually anything unlimitedly if utilized correctly, tells the Mad Titan it is on Midgard, on Earth, and he will retrieve it. Loki speaks of an Army waiting for his call, the threats Thanos made, of his landing on Earth, and lastly of the way Tony's music called to him.

Loki's voice is raw and Tony realizes that Loki was crying into his shirt for the last bit of the gods tale, and Tony hesitates before carefully maneuvering them into a sitting position where Loki is resting most of his body against Tony's, head cradled between the junction of Tony's shoulder and collarbone.

The silence lingers for a moment before Tony starts to speak, and he starts his story simply with: "I don't think my father even realized I existed most of the time."

The words slowly pour from his mouth as Tony stares off into the distance.

How dismissive his father was of him when he was young even as he got older, Tony's many unacknowledged accomplishments, the drive to learn to play the piano, the fact that Tony could do anything, build anything and his father would, at most, pat him on the head with a few dismissive words before telling Tony to let him work. Tony talks about the woman he thinks might be his mother who he can't even remember, about the crash and Obadiah. The way he starts on drinking, MIT, Stark Industries, Rhodey, Pepper, Afghanistan, Yinsen, going half-mad because of the music, escape, Obadiah's betrayal, his multiple near death experiences, his return to his piano, Iron Man.

They are pouring their hearts out to each other and Tony will later realize it all built up to that- and he is damn thankful for it, because Loki understands him, sees him, better than anyone ever has.

So Tony goes one step further and takes Loki back to his home, because Loki has heard almost everything about him, so why shouldn't he let Loki see him, and everything he is.

Tony wordlessly guides Loki to his bedroom and they slip into the Kling sized bed fully clothed and sleep until passed noon the next day.

JARVIS doesn't disturb them at all.

When Tony woke the next morning, he went downstairs and cooked breakfast.

Loki woke a little after the meal was ready and they both sat down together and ate, idly trading miscellaneous pieces of information.

They spoke of their favorite colors, their hobbies, even occasionally brought up stories of their youth until they finished eating a little under an hour later.

Tony brought Loki down to his lab and introduced him to DUM-E, Butterfingers, U and, of course, JARVIS.

JARVIS, who was introduced last, caused Loki to jump and throw an energy beam at the ceiling.

That was how they got started on talking about magic and its relativity to science.

They ended up spending most of the day within Tony's lab doing experiments and raising theories as to the effects of combining the two different fields.

When Loki created a ball of magic for one of Tony's analyzers to scan, they nearly caused an explosion. Swearing, Tony took apart the analyzer in order to ensure the system was running correctly and to 'Figure out what made the damn thing want to explode in their faces'.

Meanwhile, Loki edged away slowly before retreating upstairs to make them a late dinner.

It shouldn't have come as a surprise when Pepper walked in on them hours later.

It had taken a quarter of an hour of goading from Loki to get Tony to play the simpler, though still stylish black grand piano that sat in the foyer, but it was well worth it.

Tony got so lost in the music that he didn't hear Pepper enter and JARVIS had been muted to avoid interruptions.

The notes pouring from the piano were soothing and slow, quiet and gradually leading into one another with only small breaks and bridges to interrupt the piece.

Loki sat upon the closed lid of the piano, back turned away from the door and eyes closed, just listening to the music pouring from the piano in a piece created purely by Tony's own mind.

"Tony?...Are you…?"

Both men turned to face her, Tony's eyes wide and Loki raised an eyebrow in her direction.

Pepper flushed slightly, "That was beautiful Tony, how come I didn't even know you played?"

Tony smirked, tilting his head in Loki's direction, "Because Loks is the only one I've ever played for."

Loki slapped him upside the head.

He could handle being called Reindeer Games or the other various nicknames Tony had given him over the past few months, but he would not let Tony butcher his name.