A/N: Written for a prompt (Tony/Steve bickering). My first time ever writing Steve/Tony. So... yeah. There's a warning to you. Anyway. Thanks to Gillen for some dialogue/ideas! This is unbeta'd.

"Run a diagnostic, ALFRED."

"Do I have to?" The computerized voice asked. Tony chuckled as he clacked away at the keyboard in front of him.

"Yes, you have to. I say, you do. JARVIS remind me next time to scale back the attitude, would you?"

"Of course, sir."

"Now that's what I like to hear." Tony rolled his chair back to the small kitchenette in the workshop and popped a couple of slices of bread in the toaster.

"Whatever," ALFRED said before implementing the scan.

"Who was that?"

Tony twisted in the chair and spotted Steve lingering around the open glass door.

"Oh, that? That's just ALFRED. A new A.I. I've been tinkering with." He heard the toast pop up and rotated back around to dig through the small fridge, procuring himself a slice of cheese. He started to assemble the sandwich on the counter when he heard Steve's soft steps come up behind him.

"A new A.I.? What for?" Steve asked, peering over Tony's shoulder.

"Just something to have on hand, a kind of scaled-back JARVIS for things that don't necessarily need his incredible brainpower."

"You flatter me, sir."

Tony grinned and shoved the sandwich into the microwave and turned to face Steve. "So what brings you to the Batcave, Cap?"

A brief smile played on Steve's lips, "I'm sorry to intrude on the Fortress of Solitude, but Bruce and I sent out for dinner and I thought I'd see if you'd like to join us."

"Nah. I've already made something to eat." As if on queue, the microwave beeped and Tony turned around sliding the sandwich out.

"I, uh, I see that," Steve paused and Tony glanced over his shoulder to see Steve's face screwed up in slight disgust. "What exactly is that, do you mind my asking?"

Tony stood up and grabbed a napkin from the cupboard, turning back to face Steve with the item in question in his hands. "Quasi-grilled cheese on toast. I'm a genius!"

Steve stared at him blankly.

"You pre-toast the bread, apply cheese, microwave. Voila, grilled-cheese on toast! As I said," he took a bite, "genius!"

"That is so," Steve trailed off and shook his head. "Come on, Tony. You've been down here all day. You should eat something more than just a," he eyed the offending item, "grilled cheese sandwich."

Tony rolled his eyes and took another bite, "Thanks, Mom, but I'm doing just fine. I'm a big boy, I've been taking care of myself for awhile now."

Steve gave him a look and mumbled something that sounded suspiciously like 'Pepper' before snatching the sandwich out of Tony's hand and tossing it into the garbage bin without looking. Tony gave him just a second of reluctant praise before turning indignant.

"I was eating that, you know!"

"And now you're not. Come on upstairs."

"Seriously? What's with the mother hen routine? I'm fine. I'm sleeping, I'm eating, I'm being an all-around genius—" Tony's voice started to rise, "—what more do you want?"

"Your company."

Tony exhaled and, almost speechless, asked, "What?"

It was Steve's turn to roll his eyes. "Believe it or not, some of us enjoy spending time with you and you've spent the majority of the past week down here. You're about due for some social interaction with actual human beings. No offense, JARVIS."

"None taken, Captain."

"Speak for yourself, I'm extremely offended."

Steve's eyebrows went up. "Oh. Um. I'm sorry, ALFRED."

"Apology not accepted."

Tony laughed, bringing Steve's attention back to him.

"Come on upstairs, Tony."

"I'm fine down here, Steve."

"Not everything is about you," Steve said quietly, crossing his arms over his chest.

Tony smirked and took a step towards Steve, looking up at the taller man and fluttering his eyelashes, "Why, Steve, if you missed me all you had to do was say so."

Steve's cheeks turned pink and he started fidgeting, shifting around on his feet but not moving away. Tony gaped.

"That's it, isn't it? You miss me." He nearly crowed, grinning. He took another step towards Steve, bringing him close enough to feel Steve's quickening breath on his face.

Steve dropped his arms and his eyes darted back and forth between Tony's but he stood his ground. Tony peered up at him, gauging the look on Steve's face. He inhaled and licked his lips, noting the hitch in Steve's breath when he did so.

"Tell me if I'm reading this wrong," Tony said before putting his hands on Steve's shoulders. When he got no reaction, he leaned up and softly pressed his lips to Steve's.

There was a fleeting moment of doubt in which Tony thought that he had possibly ruined the tentative friendship that had been forming between the two. Then Steve's hands landed on his hips and Tony felt the man's shoulders relax under his grip. Tony grinned into the kiss but just before he could comment, Steve stepped forward and Tony went backwards, finding himself pressed tightly between the counter and the man in front of him. He gasped and Steve took the opportunity to run his tongue along Tony's bottom lip, like he was asking permission. Tony granted it without a second thought.

The kiss quickly turned sloppy, it was wet and full of tongue and downright dirty and Tony wouldn't have it any other way. Steve pressed against him harder, gripping him tight like he was afraid Tony would be the one to run away and while the feel of Steve hardening against him was fairly new—he hadn't done this since college, after all—he wasn't about to stop.

Tony broke off from Steve's lips and started peppering kisses down Steve's jaw to his throat and then to the junction of his neck and shoulder. He nipped at it lightly before running his tongue in a circle. Steve's groan sent a shock straight through his spine and he brought his hands down to cup Steve's ass and grind against him. Steve gasped and then cleared his throat.

"Tony, ah" the man in question bit down harder. This was no time for talking this was time for doing. Steve, sadly, didn't seem to agree. "Tony," he said in a husky voice that did incredible things to Tony's libido, "are you sure this is a good idea?"

Tony leaned his head back to look up at Steve. "I'm a man who just made microwaved quasi-grilled cheese on toast," he licked his lips, "When have I ever made an ill-advised decision?"

"Point," Steve grinned.

"Genius," Tony reminded.