It started out simple. Tony was Tony; he flirted with anything that breathed (and occasionally things that didn’t, but that’s a secret, Happy, we don’t tell anyone about that I was drunk, ok?). Strange as it sounds, Steve did still need to breath. Therefore, Tony flirted with him like he did with the rest of their little team. Ok, perhaps he didn’t flirt with Steve as much, and he attempted to keep it slightly tamer than usual to not push Steve’s buttons too much, but flirting was a part of his everyday life.
At first, it was a, “Are you a 90 degree angle? ‘Cause you’re looking right,” after a post-battle shower, or a, “You’re so cute, you make my zygomaticus muscles contract,” when Steve fumbled over technology or culture shock. It wasn’t anything serious, just Tony being Tony.
It was after he progressed to, “Let’s discover our coefficient of friction,” that Tony realized he might, actually, feel the tiniest fraction of non-platonic affection for the Star-Spangled Man with a Plan. This revelation didn’t take long to process. In the 0.6 seconds it took Steve to get the line and blush, Tony had already working everything out in his mind. He wanted Steve, more than anything he had previously wanted before. It was time to up the game. (And ok, maybe that non-platonic affection he felt was a larger fraction than he had thought, but details.)
The first real attempt at charming the tight pants off of Steve didn’t go so well. Tony hadn’t actually planned it. The day after he realized he kinda sorta maybe liked Steve, the team had met in the large main kitchen to eat together. They tried to eat as many meals together as they could, mostly so Steve could be sure everyone was actually eating, because he cared or something. Tony had wandered in last, after everyone had already started eating. Everyone but Steve, who was standing by the stove in an apron. Of course he had clothes on under it (unfortunately, in Tony’s opinion), but the very fact that he wore an apron when he cooked, most likely so he wouldn’t spill anything on his shirt, what just so adorable. When Steve turned to hand Tony his plate, Tony blurted, “Every time I see you, my cardiovascular system gets all worked up.”
Tony had spent the rest of the evening being laughed at by Clint and hovered over by a concerned Steve. “Maybe you should go to the doctor,” Steve said worriedly. “If you’re having heart troubles, there might be something wrong with the arc reactor.”
Tony dropped his head into his hands with a groan, ignoring Clint’s sniggers from the corner.
The second time, Tony had planned a little more. He actually woke up early to catch Steve in the kitchen. Steve always ate a healthy, balanced breakfast. He was also the only one who actually got up and around early. Tony chose that time, because Steve would be in the kitchen alone. Or so Tony had thought.
“What are you doing here?” he asked when he saw Natasha sitting at the table. She narrowed her eyes at him, and he hid behind the refrigerator.
“I couldn’t sleep,” Natasha said. Tony peered around the edge of the refrigerator.
“But do you have to be in here now?” Tony protested. Suddenly, he heard footsteps approaching. They were accompanied by a happy whistle. Steve. He was the only person on the planet who could be any semblance of happy at this hour of the morning. Tony took a seat on the counter, turning the coffee pot on. “Just be quiet,” he told Natasha, flinching when she glared at him.
Steve rounded the corner, stopping when he saw Natasha. “Trouble sleeping?” he asked sympathetically, like he had done this before. Natasha just looked at him. “I’ll make you something to eat,” he said, and Tony was not jealous at all.
Steve noticed Tony, blinking in surprise. “Good morning,” he said hesitantly, looking at Tony like he had sprouted a second head. Tony resisted the urge to roll his eyes, and settled on a (mostly real) smile.
“Morning Cap,” he said. He poured himself a cup of coffee, watching as Steve began to whip up several golden omelets. After Steve was good and absorbed in the eggs, Tony plastered on a smile. “You know, Cap, it’s not the length of the vector that counts; it’s how you apply the force,” he said, trying to pitch his voice low and sultry. Steve glanced over at him.
“Are you having trouble figuring out one of your inventions?” he asked, flipping one of the omelets. He paused, cheeks reddening. “Oh. Tony, it’s too early for that kind of humor,” he said, shaking his head and going back to his cooking.
Natasha gave Tony a somewhat sympathetic look as he slunk out of the kitchen.
“I don’t get it,” Tony complained, holding the test tube of chemicals Bruce had handed him earlier tightly, sloshing the liquid around again.
“Don’t spill that,” Bruce commanded. He sighed, sitting back in his chair and looking at Tony. “What don’t you get?” he asked, voice saying that he was sure he was going to regret asking. Rude.
“Why won’t any of my lines work on Steve?” Tony asked, tilting the tube sideways a bit to mix them chemicals up.
“Stop that,” Bruce said, snatching the tube away from him. He placed it in a holder carefully before turning back to Tony. “You mean those nerdy lines you keep spouting?”
“Yes,” Tony said. He stopped when the door to Bruce’s lab opened. Steve walked in, looking around.
“Bruce, I brought you a sandwich for lunch,” he said, walking over towards the desk. He glanced at Tony. “Hello, Tony,” he said politely.
“If I were a neurotransmitter, I would be dopamine so I could activate your reward pathways,” Tony tried. Steve just shot him a strange look and placed the sandwich down next to Bruce. Tony shot Bruce a ‘Did you just see that?’ look and threw his hands up in defeat.
“Thank you, Steve,” Bruce said, nodding towards the sandwich. He poured a small tube of chemicals into a beaker and left them to sit. “Please, take a seat,” he said. Steve sat in a nearby chair, watching Bruce eat the food he had brought. Tony collapsed in a chair too, sulking childishly.
Steve and Bruce started talking about boring things, like the weather and tea. Tony sighed loudly, spinning his chair around. He stopped when he noticed steam coming from Bruce’s beaker. “Hey, Brucie?” he said. Bruce glanced at him, and Tony pointed at the beaker.
“Get down!” Bruce shouted, pushing Tony onto the floor just as the beaker exploded. Glass flew clear across the room, shattering against the wall loudly. After a moment, Bruce let Tony up. Tony looked around, grinning.
“That was awesome!” he said. He helped Bruce up. “You alright? No green?” When Bruce shook his head, Tony clapped him on the back. “It’s been a while since I’ve been in the vicinity of exploding science, so thanks, buddy! I wish I were adenine, so I could be paired with U,” Tony said, hugging Bruce around the middle. “What can be blow up next?”
“Sorry, I’m just going to go,” Steve said before leaving the room quickly. Tony sighed.
“What is his problem?”
“Do you ever think that maybe he doesn’t respond to your flirting because you use those lines on everyone?” Bruce asked, unwrapping Tony’s arms from around him.
“I do not,” Tony protested. Bruce shot him a pointed look.
“You just told me you wanted to be the adenine to my U, and in front of Steve,” Bruce said slowly, like he was explaining to a child.
“I… honestly never thought of that,” Tony admitted. He frowned; obviously he’s need a new plan. After a moment, he grinned. “I know! I’ll use whatever cheesy and ridiculous pick-up lines they used in the 40s. He’ll be able to understand that!”
“Or you could just tell him how you feel and ask him to dinner,” Bruce said as he swept glass off of the floor. Tony scoffed.
“That wouldn’t work. Now quick, what kinds of lines did they use in the 40s?”
“I’m not getting involved. I’m going to reset this experiment, and stay here with nice, predictable science,” Bruce said, shaking his head the whole time. Tony huffed.
“Fine, I’ll figure it out on my own.”
“I’ll never figure this out,” Tony groaned, slamming his head on the desk in front of him. He was at the public library, avoiding Steve while he tried to discover amazing, unfailing 40s pick-up lines. He had no luck so far. He hit his head on the desk again, ignoring the librarian’s evil stare. He could buy this library if he wanted to and fire her on the spot. Instead, he typed into yet another search engine, groaning when the same dead ends popped up.
With a heavy sigh, Tony turned the computer off and twisted his chair in large circles. He stared at the ceiling, not prepared to go home just yet. He’d have to come up with something eventually…
“Oh, fuck it,” he said, sneering at the librarian’s scandalized look as he left the building.
Tony knocked on Steve’s door. When the blonde answered, Tony pushed his way past Steve’s arm and into the room.
“Please, Tony, come in,” Steve said, rolling his eyes and closing the door. He turned to face Tony. “Did you need something, because I’m kind of busy?”
Tony took a deep breath. “Steve, I think you’re… swell.”
Steve blinked. “You think I’m… swell?” he asked slowly. Tony nodded.
“I’m, uh, over the moon for you,” he added. Steve frowned.
“Get out, Tony.”
“What?” Tony asked. “Dammit, I was sure that would work.”
“I don’t need you making fun of me,” Steve said sternly. “Just stop with the fake flirting already. You’ve had a laugh at me, and now it’s time to stop.”
Tony stood with his mouth open, processing for a few seconds. He snapped his jaw shut. “Steve, I’m not making fun of you,” he said, holding his hands up placatingly. Steve rolled his eyes.
“Sure you’re not,” he said. “I think you’re swell,” he mimicked, raising one brow pointedly.
“You weren’t responding to the science and math lines, so I tried to look up pick-up lines from the 40s, but the internet failed me, so I tried to think of something that someone from then would say, but apparently my brain failed me as well,” Tony’s babbling was cut off by Steve’s hand.
“You mean, you weren’t just trying to make fun of me?” he asked. Tony shook his head. “But you say those lines to everyone,” Steve added. Tony shook his head again, and Steve removed his hand.
“Yeah, I flirt with everyone,” he explained. “That’s just how I am. But I actually kind of meant it with you.”
“Why didn’t you just ask me out to dinner or something?” Steve inquired.
“Bruce said that wouldn’t work,” Tony lied smoothly. “I figured he’d know better than me.”
Steve shook his head. “Why don’t you just try that instead of using lines on me?” he suggested. Tony blinked.
“Ok. Steve, do you want to go have dinner with me tonight?”
“I’d love to,” Steve said, giving Tony a small smile. Tony mentally fist-pumped.
A few months later…
Tony draped himself over the back of the couch, leaning up on Steve’s shoulders. “Whatcha doing, handsome?” he asked, nuzzling Steve’s neck. Steve turned his head to press a small kiss to Tony’s cheek.
“Just sketching Dummy,” he said, motioning to his sketchpad. Tony admired the drawing.
“He looks good,” he commented. Steve beamed from the praise.
“Did you need anything, Tony?” he asked, craning his head to look at his boyfriend. Tony shrugged.
“Just seeing if you were still up for dinner tonight. And maybe afterwards, I can find your nth term,” Tony said, waggling his eyebrows. Steve rolled his eyes.
“You’ve used that one before,” he said. Tony frowned.
“Alright then. Steve, I less than 3 you, babe.”
Steve scrunched his brow, trying to remember what that meant. He smiled softly, pressing a soft kiss to Tony’s lips. “I love you too, Tony.”