A/N: You should read the first two works in this series, including the A/N, first!
Warnings: amatonormativity (but he gets over it), Bucky has issues, so does Tony, spoilers for Captain America: TWS, people who require sex in a relationship
Steve Rogers had had a number of soulmates. Bucky was the first, of course. They'd been so little when they met and their palms tingled, so little that there wasn't really any discussion about it. They grew up together, and somehow they never had that conversation. They were good friends, and Bucky loved to take the dames out, telling Steve that he knew none of them were potential soulmates, but that if they could have a good time together, why shouldn't they? Steve could see that logic, but he just couldn't put his heart into it when he knew nothing would come of it. His mother told him he'd been raised too much of a romantic, and berated herself for telling Steve that if he was going to do something, it better have a purpose. "It made sense when you were five and I had to keep you from running out into the cold and catching pneumonia!" she exclaimed. "It makes no sense at all now you're a young man. Soulmates aren't all there is to life."
Steve's next potential soulmate was Peggy Carter. There was definitely a connection there, definitely something that could grow into a real relationship, but they didn't have time to try before Steve put the plane in the ice. There wasn't anything with Sharon Carter, no matter how good an idea the Black Widow thought it was, and Steve just couldn't let go of the idea that it wasn't worth the effort to date someone who wasn't a potential soulmate.
The third one was Iron Man. Steve wrote him off at their first conversation. This man? This loud, talkative, sarcastic, rude man was a potential soulmate? Naw, that had to be a flaw in the design. Maybe some soulmates were better for you than others, and this one was on the outskirts of acceptable. Loki's spear helped them all along, and then of course it turned out that Tony had Pepper. Tony didn't know about the thoughts Steve had about their potential to be soulmates, so he didn't have to apologize for them, but sometimes he wished he had anyway.
Bucky showed up again. Steve loved him with all the force of their eighty years' friendship, but he had never been so glad they hadn't pursued anything. He thought it would have broken his heart. Their hands still sparked as Bucky caught him, but the man was almost completely unrecognizable as Steve's old friend. They had fit so well before, but Steve thought there were too many ragged edges to fit together again. He let Bucky go, glad that his friend was alive, devastated at the means, and certain that if Bucky was to rediscover himself, he did not need Steve trying to make him into someone he hadn't been for seventy years to do it. Still a good Catholic boy, he sent up a prayer for Bucky every night and moved on with his life.
Around the same time was Sam Wilson. Steve liked Sam a lot. He was witty, they worked well together, really, what was the problem? They sat down to talk about it after the Triskelion fell.
"I'm sorry, man," said Sam, looking truly regretful, "but I'm as heterosexual as they come." Steve blinked.
"If we're potential soulmates, we have to be romantically compatible, isn't that kind of the point?" he asked.
"Romantically compatible we are. I'm biromantic. I could love you just fine, Steve my man. But I'm never gonna want to have sex with you." Steve pondered that for a minute.
"I could try that?" he offered. "I'm not sure if it wouldn't be too stressful in the end, but honestly sex doesn't seem that important in the scheme of things."
"Maybe not," said Sam, "but I'm holding out for a female soulmate. Sorry to disappoint. You're a good man, and I hope you find someone who can make you happy." And he clapped Steve on the back and left.
"Honestly, I wasn't ready for a soulmate when we met," Tony admitted. "I had never had one before, you know?"
Steve held him tighter.
"I knew some people dated outside of potential soulmates, and Pepper seemed so perfect, I think I tried to convince myself it was a glitch. It still might have been. She's happier now, anyway."
"I probably wasn't ready to start a relationship fresh out of the ice either," Steve admitted. "I was still grieving Peggy and Bucky."
"And when you were fresh out of the ice, I was going 'seriously? I finally meet a potential soulmate and it's the guy my dad never shut up about? How's that for irony?' and was pretty much determined to hate you," Tony admitted.
"You'd think it'd be easy, wouldn't you, with the soulmate touch. Goodness knows there are enough terrible romance novels where it doesn't exist and people have the entire world to narrow it down from," Steve mused.
"I get the feeling even if everyone had a single person's name written on their wrist or something, we'd still find a way to make it hard," Tony assured him. "People are just complicated like that."
"You? Complicated? Noooo…" Steve teased. Tony kissed him to shut him up.
Epilogue: Natasha surreptitiously downloaded a virus onto Steve's computer that forced him to read about platonic soulmates and aromantism. Steve and Sam eventually formed a relationship that was almost like being platonic soulmates (Clint wasn't sure it counted when they'd been potentials to begin with. Natasha told him Phil wouldn't have wanted him to be so exclusive. That shut Clint right the hell up. Steve had to tell Natasha not to bring up people's exes as guilt trips.). Pepper and Tony formed a similar relationship now Pepper didn't have to worry about being Tony's everything.
