Everyone knew what happened when soulmates touched each other. Whether it was hands clasping together, fingers brushing across a jaw, or lips meeting in a kiss - it didn’t matter. Any skin-to-skin contact and chests started glowing with soft, white-blue light. Soul-light, it was called. The light shone from the center of the chest. Well, if you wanted to be completely accurate, the light shone from a little to the left of the center of the chest. From directly over the heart, if you could fucking believe it.
Soulmates touched and their chests glowed for each other and everyone lived happily ever after.
Tony honestly thought it was a lot of bullshit.
For every happy soulmate story, there were two that ended in tragedy. For every Buttercup and Westley there was a Paris and Helen or a Romeo and Juliet. Literature and history were filled with countless stories where a touch was all it took to start wars and tear families apart. Lives lost, cities razed, spirits broken all for the chance, the possibility that all you needed to be happy was one other person. Two chests glowed and what did it matter if Rome burned?
The scientist in him hated the concept of soulmates. Tony raged against the idea that the entire course of his life might change just because of a random biological response to another person - a biological response that nobody fucking understood anyway.
Tony didn’t need a soulmate.
Having a soulmate did not guarantee happiness; Tony’s own parents were proof enough of that.
Except… a small, dark, hidden, silenced part of Tony yearned for a soulmate with a fierceness that had the power to ruin him. Because it was intoxicating, the thought of having someone that would move heaven and hell to be with you and damn the consequences. To be loved that way and with such fervor would be addicting and Tony craved it desperately and in secret. And realistically, Tony knew his only hope for that kind of love was his soulmate, because who else would bother looking at Tony and seeing something of value?
Tony grew up and his chest stayed dim.
Tony met Rhodey and Pepper and had minutes, hours, days where he hoped that one of them might be more to him (might be it) but no, his chest stayed dim. His chest stayed dim and a tiny part of him was thankful because didn’t Rhodey and Pepper deserve better?
Tony lost his parents and suddenly, the lack of light in his chest seemed all the more glaring. His chest stayed dim and it felt like a condemnation.
Tony built the best weapons in the world, attended lavish parties, and had one night stands with beautiful men and women and it helped take his mind off the fact that after 40 years, his chest was still empty and that every day, absolution slipped further and further out of his grasp.
Tony woke up in a cave in Afghanistan with a hole in his chest and wires coming out of it and felt his blood run cold, dread curling heavy and low in his stomach.
Science still hadn’t worked out many of the finer details of how soulmates or soul-lights worked, but what was known was this: soul-lights operated on a positive feedback loop. That for one person’s soul-light to shine, their soulmate’s soul-light also had to glow. The lights bolstered each other and grew brighter the longer soulmates touched. The connection between two soul-lights was supposedly “a beautiful metaphor for love and for the soulmate bond,” but what it actually meant was if one person’s soul-light wasn’t visible, their soulmate’s chest wouldn’t glow even when they touched.
Soul-lights could be temporarily blocked (e.g. completely obscured underneath too many layers of clothing) and occasionally, rarely, they could be permanently extinguished. Sometimes burn victims that had extensive skin grafts on their chests lost their soul-lights.
If you lost your soul-light before you found your soulmate, it meant that you never would find them. Because even if you met and touched them, your soulmate’s soul-light would never appear since it had no responding soul-light to feed off of. If you lost your soul-light and didn’t already have a soulmate, you were shit out of luck.
So Tony looked at the thing sitting in his chest, keeping him alive, and instinctively understood what it meant.
He’d lost his ability to produce a soul-light.
He would never find his soulmate.
He was shit out of luck.
Tony tried processing it. He tried thinking rationally about the loss of something he never had and never truly expected to have, but the walls of cave started closing in on him and he choked on the violent nausea welling up inside of him. Tony had to consciously remind himself to keep breathing. He closed his eyes and fought against the part of him that wanted to give up now that he had lost all hope.
Because that was what losing his soul-light meant.
Tony’s soulmate was gone and with them went all Tony’s naive dreams of completion and redemption.
Tony couldn’t believe that despite being on the verge of death and held hostage by terrorists, he was more upset about the loss of his fucking soul-light. Typical.
The arc reactor he built in the cave glowed the same shade of light as a soul-light and Tony could barely look at it without his stomach roiling. It was always there, always glowing - a cruel, taunting reminder of what Tony had lost.
“You got a family?” Tony asked Yinsin.
“Yes, and I will see them when I leave here. And you, Stark?”
“No. And no soulm- no.”
Yinsen looked thoughtfully at Tony’s chest, “So you’re a man who has everything…. and nothing.” He paused and gestured to the arc reactor. “I am sorry, if I had known I perhaps could have-”
Tony cut him off, “It’s fine. I don’t think it would have mattered either way.”
Yinsen laid a trembling hand on the armor, over the glowing arc reactor, “Don’t waste it… don’t waste your life Stark.”
Tony came home with metal in his chest instead of a working heart and stopped building weapons.
Tony built a new arc reactor and a new set of armor.
Tony became Iron Man.
And throughout it all, Tony’s chest glowed because when he rebuilt the arc reactor, he made sure to keep the light - the soft bluish-white light just like that of a soul-light. These days, Tony wore it proudly. The arc reactor was a love letter to the one thing in his life that still had any meaning - his tech, the armor. Tony didn’t have a soulmate. He would never have a soulmate. But he did have Iron Man. Iron Man was everything Tony Stark wasn’t (good, selfless, a hero) and Iron Man deserved to have a soul-light even if Tony Stark didn’t.
The public found it by turns obscene, fascinating, and liberating. Editorials, blog posts, TV reporters, and religious figures across the country and the world all weighed in, either decrying the arc reactor as a perversion of the purity and sanctity of soul-lights or praising it as a bold, much needed statement on the irrelevancy of soulmates.
For better or worse, soulmate or no, Tony’s chest would never be dim again. Tony took all his frivolous, juvenile, hopeless dreams of a soulmate and locked them up behind tall walls deep inside of himself.
Tony didn’t say anything and Pepper still understood. “Proof that Tony Stark has a Heart,” read the case containing the first arc reactor. On his better days, Tony looked at it and saw confirmation that he would be okay without his soulmate. And on his worst days, well, Tony didn’t look at it at all and wore something heavy and thick enough to obscure the light in his chest.
Some nights, Tony would jerk awake, his heart racing and half-remembered dreams of heat and sand and constant pain lingering in his mind. He would lay awake in his big, empty bed and gradually his breathing would even out and his heart would slow. At night, Tony’s room was always bathed in the blue glow from the arc reactor and Tony clung to it, let himself be soothed by it. The arc reactor was many things - a symbol, a middle-finger to the world, a benediction, a curse, Iron Man - but it was ultimately irrefutable proof that Tony had survived.
And so the light would lull Tony back to sleep. It was comfort and torment at the same time and both feelings mixed and twined until Tony could barely tell where one began and the other ended.
When Obadiah ripped the arc reactor from his chest it seemed like the harshest sort of irony. Tony was literally going to die because his chest was empty and dim.
“I am Iron Man.”
Cue more hysterical articles, editorials, and blog posts.
The day Tony realized the arc reactor - his own, handmade soul-light - was poisoning him he didn’t know if he should laugh or cry. He settled on getting very, very drunk.
Tony found a way to fix it of course. After all, his life depended on it; depended on keeping his chest lit.
Soulmate Dysfunction Disorder they called it - the inability, for some reason or another, to find your soulmate. These days, SDD’s position as a diagnosable medical condition was heavily controversial. Critics pointed out numerous examples of people that had lived complete, successful lives supposedly without ever meeting their soulmate (the Nikola Teslas or Florence Nightingales of the world) and entire new progressive movements were dedicated towards phasing out the traditional view of soulmates as perfect romantic partners.
So these days, for a lot of people, not being able to find your soulmate wouldn’t be a problem. But for many more - for most of the rest of the world, actually - it was. And so SDD remained right there in the DSM-5 as proof that Tony was broken.
Tony read SHIELD’s report on him; the report that “disqualified” Tony Stark and subsequently Iron Man from the Avengers Initiative. “Textbook narcissism” - was it narcissism if you were objectively smarter than everyone else? But fine, okay, whatever. “Prone to self-destructive tendencies” - wasn’t everyone? And in Tony’s defense, he had been dying during most of that self-destruction. “Volatile” - sure. “Unable to work with others” - more like unable to tolerate stupidity, but not not true. And then there, tacked on to the end of the laundry list of deficiencies: “Permanently incapable of forming a soul-bond” - and, well, Tony didn’t have a quippy response for that.
Then SHIELD lost an ominously glowing cube to an alien demigod and suddenly Tony wasn’t quite as unqualified for the Avenger’s Initiative anymore.
Steve Rogers was cold, stubborn, and infuriating. He was also quite possibly the most beautiful person Tony had seen in real life. But maybe worst of all, Rogers was a good man. He was everything Howard had said he was (damn Tony hated it when his father was right). Steve Rogers: the living legend that lived up to the legend. And it was awful and horrible because Tony found him captivating. Steve Rogers was a puzzle Tony wanted to solve. And so Tony pushed and prodded because that was what he did. Tony applied force at people’s pressure points until they snapped because it was the only way to know who someone was; the only way to see what people hid behind their masks.
Tony was good at it, at pushing people. And Rogers, well Rogers responded beautifully. Very few people had the nerve to go head to head with Tony - the prerogative of being smarter, richer, and better looking than everyone else - but Rogers pushed right back with a dangerous glint in his eye that Tony found fascinating. Tony thought he could get used to this, to having Rogers’ knife-sharp attention and all his steely determination focused exclusively on him.
But once they were done, after they had both said their piece, Rogers’ words still echoed uncomfortably in Tony’s head - “Stop pretending to be a hero.” And Tony definitely hadn’t missed the way Rogers’ gaze had repeatedly flickered to his chest - to the light of the arc reactor - during their argument, a troubled frown distorting perfect features. It didn’t bode well for the future, but at the moment, no matter how much he wanted to, Tony didn’t have time to analyze Rogers any further. They had the small matter of an alien invasion to deal with.
A split second of eye contact and Tony knew exactly what Rogers was thinking. Tony’s bright repulsor blast arced perfectly off of Rogers’ shield.
Apparently, in battle, they worked together seamlessly. Of fucking course they did.
Get through a conversation without yelling at each other? Not a chance. But efficiently fight off an invading alien horde? Easy.
Seeing Rogers fight was like watching poetry in motion. Although, Tony wasn’t particularly partial to poetry so maybe he should compare Rogers to a flawless line of intricate code or the delicately crisscrossing lines of one of Tony’s schematic. Or maybe a dancer, Tony mused as he blasted an incoming Chitauri vessel and sent it spiraling to the ground.
Whatever hackneyed metaphors Tony’s brain conjured up, it didn’t matter. Rogers was magnetic and Tony couldn’t have looked away from him if he had tried
Rogers barked an order over the comms and his natural, firm tone of command sent a flicker of heat racing down Tony’s spine in what had to be the most inappropriately and inconveniently timed moment of attraction in the history of the world.
And then came the nuke and the portal and the bone-deep knowledge that this time, there was no clever solution - no way for Tony to think, talk, invent, or fight his way out of this problem.
“Stark, you know that’s a one way trip.”
Tony knew. Tony called Pepper and when JARVIS couldn’t reach her, Tony tried not to think about his soulmate. He tried not to wonder what he could have done differently. He tried not to regret. Tony closed his eyes.
Tony jolted back to consciousness. Fuck. Apparently, he was alive. He knew he was alive because everything hurt too much for him to be dead.
Tony opened his eyes and Rogers - Steve - smiled at him, sweet and relieved.
“Please tell me nobody kissed me.”
But if Steve was offering… Wait, no. Fuck, how hard did I hit my head?
“We won,” Steve said.
Tony said something in response - was he rambling about shawarma? Whatever. Tony wasn’t really paying attention to the words coming out of his mouth. Instead, his entire being was focused on that smile. It was the first time Tony had seen Steve smile. It was fucking incredible. Tony had a moment of complete and utter insanity where he thought he might just be willing to fly a second nuke into cold, dead vacuum of space if it meant seeing Steve look at him like that again.
That was also the moment Tony thought he might just be screwed.
They shook hands, Steve’s grip warm and steady and Tony felt a frisson of something (recognition? heat, want, need ?) spark deep and low within him. And so, even though it was the last thing he wanted (Tony wanted to keep touching Steve, to forcibly haul him back to his tower and keep him there until Tony understood), Tony plastered on a smile he didn’t mean, let Steve’s hand fall from his own, and said his goodbyes.
The Avengers fractured. Thor to Asgard, Romanoff and Barton back to SHIELD, Bruce to parts unknown (but with a promise to come back for his new lab in Stark Tower), and Steve on the most depressing cross-country road trip possibly anyone had ever taken.
And Tony? Well, Tony carried on doing typical billionaire genius philanthropist things as he struggled to rebuild - the city, his tower, himself.
Something strange had happened during the battle. Tony thought something might have cracked inside of him. It felt like a dam had burst and during quiet moments, when Tony’s mind wandered, he couldn’t seem to stop himself from picturing the curve of Steve Rogers’ lips and a future that wasn’t his to want.
And if late at night, when Tony lay awake, unable to sleep because of the dark, desolate visions of space that had replaced his nightmares of Afghanistan, he thought of Steve - of where he was, of what he might be doing, if he would pick up his phone if Tony called - then it was nobody’s business but his.
No amount of digging through classified SHIELD files could tell Tony the one thing he desperately wanted - no, needed - to know: who was Steve Rogers’ soulmate? He had to have one (Peggy? Barnes?) but the history books had been surprisingly silent on the subject of who Captain America’s soulmate was. And even more astonishing, Howard had never said anything about Steve having one. But he had to have had one; a soulmate that was. Steve - Captain America - was Perfect (with a capital P) and Perfect meant having a soulmate.
It frustrated Tony to no end, this simple but seemingly unanswerable question. And even more exasperatingly, Tony couldn’t figure out why he was fixated on it. After all, what did Captain America’s soulmate have to do with him?
A while later it occurred to Tony that if Steve had had a soulmate, then it meant he had also lost a soulmate. What’s worse , Tony wondered, having them and losing them, or never getting the chance to have them at all ?
But if Steve had lost his soulmate, then maybe he wouldn’t mind- No. Tony shut down that train of thought quick. In no world would Captain America would see Tony as anything other than a teammate and maybe, if Tony didn’t manage to fuck it up, a friend.