Before the serum, Steve was honestly little more than a small man with big ideals. Even he could admit that. He had never felt that he had the right body to do what he wanted to– joining the army had seemed like the most important thing in the world to him in the wake of WWII, but certain rules kept him and people like him out. And even when he finally had the body that felt right for him, he wasn't exactly participating in the effort in the way he had anticipated to.
When he finally made it to the front he had definitely not expected to be a performing national icon. But super-serum-Steve was better than a weak-asthmatic-Steve any day of the week, at least in his book. It wasn't like he wasn't doing at least some good for the sake of the cause. Of course, that reasoning only worked for so long before he decided he had to take things into his own hands. Morale and money were important, but he needed to be doing more, especially when Bucky's battalion went missing. So he did.
Decades later, with the war long over and having been frozen for seventy years, Steve was really only just beginning to notice the real side effects of the changes the serum had made to his body. You see, Steve was born an omega by nature. No huge surprise to anyone there, to be sure. His smaller, weaker body type was exactly the sort that those old films he used to watch depicted as the weaker sex. The one that had to be saved. The one that was by no means considered to even be capable of being the 'hero' type, regardless of whatever previous strengths they had shown. The omega was never the one to save the day, and that was just the way things were. But an unforeseen side effect had occurred when the serum, a concentrated cocktail of alpha genomes that had been strategically injected into his body, altered his physical appearance. It had also impacted his hormone balance.
He had never before been without suitable distraction and near constant physical exercise to keep his libido in check. So when he began to experience the clash of the two types of hormones in his body Steve found himself wrought in a veritable tsunami of alpha instincts that sought to dominate the true omega ones he'd been born with. Naturally– or unnaturally, as the case may be– this all resulted in an... interesting personal turmoil. As an omega he had been a late bloomer in terms of puberty to begin with, and a result he had only experienced three or four regular heat cycles in the past. This left him ill equipped to handle things when they came again warped and intense in his genetically unfamiliar body.
He was slowly learning to deal with it. He took a strong dosage of suppressants that had been developed by S.H.I.E.L.D when they learned of his special circumstances, and he was granted two weeks leave instead of the standard one to preserve his privacy with the Avengers team. Steve generally only took that time as needed for the particularly difficult months. The sort of months where his scent would grow so strong that it impacted even the bonded and mated alphas in his vicinity. There were some months where there was a legitimate concern that the delicate dynamic of the team would be jeopardized by competition, battles for dominance, and sexual interactions among team mates– a major concern especially since they had only recently resolved the majority of the issues that plagued the Avengers team. Steve vowed that he would not be the reason for their problems, so he did anything in his power to preserve the sanctity of the group.
It seemed as though the only issues they hadn't been able to resolve yet lied between him and Tony Stark. The clash of personalities was one thing, but the complete incompatibility of instincts between the two was quite another. Stark was a very dominant personality type, and even though he smelled alpha on Steve outwardly, he subconsciously seemed to recognize Steve's true nature and wanted to overpower it. That was all well and good, but Steve wanted to keep his omega status a secret. Prejudice seemed to have slowed in contemporary society to some extent but he still feared what might happen when the world discovered the truth. He didn't want to lie to his team, he just let them assume whatever they wanted and neither confirmed nor denied anything either way. For the most part the other Avengers seemed to think he was at least a beta with a high sense of self-righteousness, but perhaps they thought it rude to ask.
The only team member who knew anything about Steve's situation was Natasha. He hadn't really wanted her to know, but everyone knew it was only a matter of time before the clever assassin got the information she wanted after she decided she wanted it. Especially if you were actively trying to keep that information from her. It was fine since Fury had insisted he confide in someone for the sake of his own mental health anyways. If he was being honest, it was truly nice for him to have someone to talk to about things when things got rough. The redheaded alpha was particularly sympathetic because she faced her own prejudices being a biologically female alpha, and there was practically no tension between them due to the strength of her bond with her own beta.
The secrecy, however, did not sit well with the rest of the team once they found out that Natasha was aware of something they weren't privy to. Thor actively demanded he be told when he sensed something was up, though he backed down at least a little bit when Steve insisted he would share when the time was right. Natasha handled Clint's suspicion easily; she only need raise her eyebrow for him to get the message though it was clear he expected to be informed eventually as well. Bruce was the only one who largely kept to himself, though the way he paid careful attention when conversation was taking place betrayed his quiet interest.
It was Tony in particular who seemed to become increasingly agitated in Steve's presence once he realized there was something being kept from him. He was especially difficult upon walking into a room where Steve and Natasha had either promptly stopped talking or glanced his way and gotten up to leave in order to continue their conversation elsewhere.
One such incident would lead to the culmination of the tension between the two of them.
oOo
"What's up, lovebirds?" Tony snapped crassly, eyeing Steve who sat next to Natasha at a stool near the kitchen counter. He found that he was unable to stop himself from bristling when the blond immediately got thin-lipped and quiet.
"Shove it, Stark," supplemented Natasha helpfully, laying her hand on Steve's.
Steve merely flushed and turned away, murmuring something Tony couldn't quite catch to the redhead.
Natasha was also one of the few people in the world who knew about Steve's ultimate issue with Tony. He believed the hormones that swirled within him were causing a warped sense of attraction towards the other man. Being an omega at heart, he knew that there was always a sort of arousal that could be stimulated by minor things– such as the presence of an alpha who had no mate– but what he felt bordered on ridiculous. Not to mention the added complexity of the new alpha instincts he was trying to deal with– which changed that arousal from simply wanting to spread his legs for the other to the unfamiliar feeling of wanting to fuck Tony senseless himself.
He shook his head quickly. He wouldn't even justify that thought by indulging that fantasy. It was more than that for him anyways. He genuinely liked Tony, but his screwed up hormones just made things too complicated for him to try and comprehend. Besides, Tony always reacted so hostilely to him that it hardly seemed worth it to try.
It's not as though Tony was in want of partners anyway. He could probably have anyone he wanted in five words or less. Steve had seen numerous tabloids and articles that told tales of Iron Man's sexual exploits, old and new. The women he was photographed with were always gorgeous, perfect creatures that looked like they probably bathed in literal gold– and that clearly meant that Steve was not his type. The parade of women Tony had bedded would likely extend down the length of a whole street, and with practically no experience of his own how could the virginal Steve Rogers possibly compare to that?
Sure the number of strange women that had seen roaming around the tower after a night of proverbial 'love-making' had decreased significantly since the team had actually gotten together and moved in, but... actually, Steve realized, he couldn't remember the last time he saw a strange woman leaving in the early hours of the morning.
Steve tuned out the rest of the conversation around him and removed himself from the counter when Nat and Tony fell in to their usual game of all-out banter, using the chance to escape. It was only a matter of time before Tony pulled his usual stunt of flirting openly with the assassin, and with a heat cycle so close to starting he wasn't sure he could handle being in the same room with the openly lewd Stark who would become all leering and thinly veiled sensuality.
Especially since the attention was in no way intended for him.
As he quickly sidled past by the other man and out the door he tried desperately not to shudder or stumble. He'd caught Tony's scent, which momentarily sent him reeling. Tony looked good in his suit. His tie had been loosened and his shirt untucked, but he pulled off the slightly-rumpled-yet-formal look well. Steve couldn't help but imagine pulling him down by the strip of red fabric, the alpha latching his hands in the short hair at the back of his head, and– no, stop that.
He trembled when Tony met his eyes briefly and– perhaps in an attempt to hide the shaking in his hands– offered a short two-fingered salute from his brow on the way by. Tony, who had still been speaking to Natasha, stopped mid-sentence in confusion. He fumbled for a response to the absurdly random gesture.
As Steve made it safely by and out the door, he berated himself.
What the fuck. Was that supposed to be casual?! He was better off just locking himself in his room and never coming out again. In fact if he was honest with himself, the less time he had to spend with the other man the better off they'd both be.
oOo
Once the tall blond was gone, Tony recovered and found his voice again. While his previous line of thought and sentence were completely forgotten, he looked back up at the redheaded female and performed a mock salute towards her in the same manner the Captain just had to him. Perhaps to try and cover for his disconnect. Steve's scent on his way by had caught him off guard– it was certainly alpha as far as he could tell but there was something not quite right about it. Still, he found that he wanted to drown himself in that scent regardless. It made his mouth water, even as an alpha himself. To his surprise Natasha stifled a small smile.
"He's not very good at secrets," Nat sighed vaguely.
"Ah-hah!" Tony moved toward the opposite side of the counter and leaned against it. He was close to her but far enough that she wouldn't consider him invading her space and physically remove him from it. "So, you admit you're keeping secrets then?"
"I never denied it." Her face was impassive.
"Touché. Look, Capsicle looks like he has something he wants to say and he won't talk to me. Trust me, I've tried. I'm just saying it would be easier for everyone if he would just get it over with already. So you should just tell him to spill. What kind of problems could Captain America have that he can't just share with the class?"
"It'd be easier for you if he'd tell. But trust me, it's not that simple," she snorted. "Steve will let everyone know when he feels like the time is right. I know that's damaging to your fragile ego, not being in the loop on something for once, but that's just the way things have to be right now." She patted his cheek hard, no doubt playfully mocking him, but he was too frustrated to come back with a biting remark in return. Ultimately he knew she was right and it pissed him off. "Now if you'll excuse me, I have some actual work to do."
She walked out the same door Steve had awkwardly excused himself out of moments before without another word. Though she did give him the goofy little salute. She slipped a small disposable phone out of her pocket and dialled before she turned the corner and was out of sight.
Once alone, Tony grumbled to himself and raked a hand absently through his hair. The blond had been avoiding him since they all started to stay together in his building. Steve was distinctly careful not to be alone with Tony, he was always quiet when Tony was in the room, and if he did speak he was always cautious and calculating in everything he said. This was infuriating because he'd honestly thought that he and the Cap had been on better terms since they had worked together, saved the world, and sent Thor and Loki back to Asgard... Apparently he was the only one who felt that way if the other's distant attitude was anything to go by. Sure he'd been a bit of an ass and things had been rough between them at first, but alphas almost never played nice together initially. That was just a fact of life. He was willing to move past it, so why was Steve still hanging on to a grudge?
After the imminent danger was over with, Captain America and Iron Man having worked together to restart engines and then fought back to back, he'd felt something for the other man. He couldn't quite put a name to that something at the time, but having Steve working daily in close quarters (and practically demanding his full attention by dutifully avoiding him) showed him that it was a sort of attraction. It was only a matter of time before that attraction turned into something even deeper. He was aware that Steve had his own hang-ups and some skeletons hidden deep in his closet but hey– so did Tony. Life had not exactly been the easiest for either of them.
He briefly entertained the idea that perhaps that was what caused his initial attraction to Steve in the first place. They could understand each other on a level that Tony hadn't been able to find in many other people. From there was Steve's kindness, determination, and his ability to take and dish back anything Tony threw his way. It all appealed to him. Before Steve, Tony had never felt like committing to a mate was for him. But he could see the potential for a future with Steve, or at least he had before Cap had inexplicably shut him out.
The worst part of it was he wasn't even sure what caused Steve to pull away. It wasn't like Steve could have sensed his growing attraction to him. Tony was the king of suppressing his emotions so that others couldn't use them to manipulate him. Plus the super soldier had not pulled away from anyone else. Natasha was apparently his favourite and she was an alpha so it didn't make sense for that to be the only reason either.
His hands ached and his skin itched as he got annoyed over his situation again.
He pushed away from the kitchen counter and moved towards his workshop. As he grew more irritated he needed something to occupy his hands. Some time alone might do him some good anyways, Pepper had had him out on business all day and he was decidedly sick of corporation. The ol' suit probably needed a little tuning up since its last use anyways.
He stripped down to his undershirt, leaving his coat, dress shirt, and tie crumpled on the desk nearest the door and set to work. JARVIS immediately began to spout updates one by one, but it was a matter of seconds before Tony muted the sound. As he tinkered he tried to keep his mind from drifting to the blond, to those blue eyes that saw right through him, to the muscled body he longed to have over him or under him or... anywhere in the vicinity of him, really.
So he failed at keeping Steve out of his thoughts. Of course he did. But there was something to be said for trying, wasn't there?
Before long he had subsequently failed to realign a loose wire correctly three times in a row. A task that should have taken him literally no thought and no more than fifteen seconds flat. This was getting ridiculous. He decided then that he was going to have to do something about... all of this. Steve couldn't avoid him forever, not without at least telling Tony the reason why. Not when Tony could still feel the weight of this thing between them, not when there was still a chance that Steve could be feeling it too. Tony was used to giving up on things he wanted but perceived he couldn't have without an honest fight, but this wasn't going to be one of them.