Hi everyone! This is my first time writing an Avengers fanfic so I hope you enjoy.

I am such a fan of science bros so I thought I would try my hand at writing a bit of a series about Tony and Bruce's friendship. Natasha and Bruce's establishing relationship was just something that crept up.

Anyway, I read a comment one day of how in the first movie, Tony really acted like a big brother to Bruce. That really struck true with me so I thought I would give that a try, writing their friendship as brothers. Because I really do see them as brothers. Even though Tony is the irresponsible one, I see him as really protective of Bruce.

Also, I have written Natasha differently from the way I've seen her written. I see her as more expressive in the movies. She has facial expressions, even though she is often calculating, and she also seems to have a genuine affection for Tony as well.

So, all in all, let me know what you think in comments, and if y'all would like it continued!

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Natasha was more than slightly ashamed to say it was Thor that pinpointed it all before everyone else. It wasn't that Natasha hadn't noticed. She was the infamous Black Widow after all. She noticed minutiae details almost as much as Clint.

Probably more in this case because Clint was slightly oblivious to some social clues. In a battle, he was flawless, calling out patterns and noticing threats fifty clicks away. But socially? The poor guy took forever to put it together that Laura, his current wife, didn't actually need all the sugar she kept on asking to borrow. If it wasn't for Laura's advances becoming less and less subtle until she was the one that asked him out on a date, Natasha doubted Cooper or Lila would be here.

Still though, despite Natasha noticing it all, she still didn't pinpoint it the way Thor did. It was more than a little annoying. Thinking back on it all, she really should have, but she was going to plead ignorance in sibling interactions if teased about it (Clint, I'm death glaring at you).

In the beginning, Tony Stark and Bruce Banner's friendship was logical, even if a slight improbable. They were both geniuses so of course they would have a common ground. Natasha had thought though that Tony's tactlessness might scare Bruce. The guy was downright skittish. She knew he would have run in that shack back in Kolkata if he hadn't figured out that it hadn't been, 'Just you and me'. Then, he had taken great pleasure in unnerving her because he was scared by feeling trapped.

Immediately, it appeared she was right about the two of them. Bruce had shrunk back in on himself when Tony had babbled on about a 'giant, green rage monster' and remained fairly quiet the rest of time he was in the presence of everyone.

However, after the whole battle on the Helicarrier, Tony predicted his movements better than everyone else on the team, including the strategist that was Captain America.

So, when Bruce had asked for his duffle bag from her, saying he was going to spend a bit of time at Stark Tower, Natasha had been slightly surprised, though understood that they may have bonded over their love of science and had also been unwillingly pleased. For some unknown reason, she didn't like the thought of Bruce slinking off to some hidden corner of the world. Maybe it had to do with that he did just help save all their lives. He deserved a bit of comfort. And even though she would never say it out loud, Tony could be annoyingly likeable and she had figured out pretty quickly that he had a bit more heart than he often showed. They might even do each other good.

That was what she was hoping for anyway. Secretly, she was worried that she was going to see the Hulk on television, smashing away at Stark Tower.

Still though, even she could never have predicted what she would walk into that day on the Helicarrier when Fury insisted they had a team meeting, exactly two months after the battle with Loki, to try to maintain the connections that they formed when defeating the Chitauri. Natasha could see the logic behind that. After they stopped their bickering, they worked seamlessly together so it would be stupid to let that go.

Walking through the sliding doors, Clint right by her side, she took in everything in one quick sweep. Steve Rogers was at the right of the conference table, closest to Fury who was standing at the head of the table. Steve was forever the soldier, straight backed, clear blue eyes attentive and bright. He nodded at both her and Clint, and a genuine sideways grin was evident on his lips.

Thor was directly across from Steve. All though he was a warrior as well, he obviously perceived no threat as he lounged in his chair, smiling openly at her and Clint. Natasha smiled softly back at the both of them, particularly at Thor, because she couldn't help but feel happy that her arrival hadn't made him feel in danger, despite being the assassin she was.

'See, I told you we were too early. We were even here before Red Riding Hood and Robin Hood.'

She didn't have to turn to see who was talking, but she did anyway.

Tony wasn't even looking at her and Clint. This was surprising in itself because usually when he chucked out nicknames, he always watched to see what sort of reaction it would garner. Instead, his arms were crossed while his large brown eyes were dark as he pouted at the oak table like it had done him a great wrong.

If Natasha wasn't Black Widow, she would have had to do a double take to see who it was sitting next to Tony.

Bruce looked different. His curls were still wild, but he was dressed fairly nicely, a simple blue shirt and black jacket, both which looked the highest in quality while his hands were for once still. That wasn't it though. It was his large smile, so out of place for such a usually unassuming man. Though he wasn't looking up, it was very bright. He was seated so close to Tony that their arms were almost brushing up against each other. He wasn't so slumped. His eyes were unavailable for her to see because they were closed in what looked like mirth.

Her attention was redirected from Bruce to Tony, whose eyes had darted away from the table to glance at Bruce. Invisible to everyone else but Natasha, she saw the skin around his eyes crinkle the way it always did when he was happy. This usually just meant Pepper walked into the room, but the strawberry redhead was as far away as she could be. All though Tony kept up an over-exaggerated pout, his arms loosened and he playfully slumped against Bruce's side.

The most shocking thing about this scene wasn't that Tony was easily touching someone who wasn't Pepper or even Rhodey, though it was a close second. No, the most shocking thing was that Bruce didn't even flinch. The man usually ducked down if someone jogged too close to his personal space let alone touch him.

The action simply caused Bruce to peek up at the engineer, eyes bright with something Natasha couldn't immediately identify and didn't have time to as Clint spoke up.

'As hilarious as ever, Stark,' he remarked, jumping into a seat, somehow balancing on the back despite it being a tilting chair. 'Tell me, do you rehearse these before you come in because you have so little things to do?'

Natasha silently slipped into her seat as Tony perked up, recognising the impending verbal battle.

'I'm a brilliant multi-tasker, Legolas,' he drawled. 'I can quote the first thousand numbers in pi, utilize quantum tunnelling effects to produce energy, straighten Bruce's hair,' here, Bruce snorted, causing Tony's eyes to crinkle more, but he didn't miss a beat as he continued, 'invent a new alloy that will compete with vibranium, choreograph a better dance routine to Single Ladies, calm down Pepper about the half dozen SI meetings I've missed and still come up with lovable nicknames for you and Itsy-Bitsy.'

Clint could easily come up with a comeback. Natasha knew he could. He had at times made Phil Coulsen, one of the most apathetic people Natasha had ever met, actually get an eye twitch.

It happened once when Clint had started doing a mission debriefing all with a flawless Irish accent because the mood had hit him. It got to the point that Coulsen could hardly understand him. Each time Coulsen calmly asked, 'Please speak, English,' Clint proclaimed, 'Aye, laddie, I am!'

Natasha would have looked at strangling Clint with the piece of wire she hid up her sleeve if it hadn't been so damn entertaining to actually see Coulsen get slightly flustered.

Now, Clint's face broke into a large grin, eyes appraising as he took in Stark. 'You choreograph dancers?' He settled with saying with just a hint of a laugh in his words.

Tony raised his arms out wide in a dramatic gesture, accidentally clipping the end of Bruce's nose. 'Have you not seen my Stark expo? And here I thought you saw everything!'

Fury looked like he was about to have a seizure when Bruce jerked back, but the physicist simply rolled his eyes fondly and leaned back so he was out of range of Tony's gesticulating hands. Steve's mouth was opening and closing like he was trying to decide where was the best place to jump in to try to redirect the conversation to something that was actually Avengers' business. Thor was just grinning at what was being played out.

'I see everything of value, Stark,' Clint corrected, his breath only hitching minutely when Tony had connected with Bruce. Once again, Natasha knew she was the only one that noticed. Her senses had jumped about ten-fold when it happened and she still felt ready to spring from her seat even though it looked like Bruce was the furthest thing from becoming the Hulk.

'And I reiterate: have you not seen Stark expo? Tony magnanimously flicked his fingers towards Steve. 'If I'd choreographed the USO girls, all those films wouldn't be so damn embarrassing. No wonder he blushes so much on the shows. I would too if I had those dance routines going on behind me.'

The comment had the effect Tony was obviously aiming for. Steve blushed instantly.

This time, Clint didn't hold back. He burst into laughter, dipping his head slightly, eyes once again intently on Tony.

Tony smirked back. Natasha could see the thread of uncertainty there as though he didn't believe that Clint was going to leave it at that. For Tony, nothing was ever that simple. However, Clint just slipped down into his seat, smirking brightly at her.

'Can I take this one home with me, Tasha?' he asked, jerking his head at Tony, who actually seemed nonplussed at the comment. 'He's fun to play with.'

'Just don't kidnap him in front of the authorities,' she intoned wisely.

'Hey!' Fury's distinctive tone cut in while his one eye sharply swept across them all. 'Do you think we could actually start the meeting? You can all fight and whine after.'

Steve nodded a bit too eagerly while Tony's mouth popped open, most likely to make some smart comment in hopes of getting a rise out of Fury this time.

However, Bruce, against all laws of nature that Natasha knew, actually initiated contact and subtly nudged Tony with his shoulder. Then, Natasha witnessed the strangest thing she had the entire time she had entered.

Tony listened. His mouth shut and even though his scowl was prominent, leaned back in his chair, glaring mutinously at Fury though it should have been technically directed at Bruce. He hadn't been cajoled, persuaded by numerous enticing offers and well, everyone knew how well it went for people who threatened the man who created Iron Man to do what they wanted. Natasha personally knew there was a file there somewhere on every person dumb enough to actually threaten Tony Stark.

However, here he was, listening to the unassuming man next to him without even a glare sent Bruce's way.

Despite everything, Natasha couldn't help but be slightly entranced by Bruce. He was one of the first people she had never been able to read, and the others she hadn't been able to was when she had been a young girl in the Red Room.

She had tried to brush it off. She had been distracted by Loki brainwashing Clint. Of course she had. She had been a little overwhelmed to be confronting the man that contained such a force that was not able to be taken down. Who wouldn't?

However, as she looked at the man with honeyed brown eyes, wild curls that couldn't be tamed, hands clasped over his stomach as he watched Fury peacefully, she was overwhelmed with the feeling to just … she didn't even know. The feelings were just so foreign. She couldn't even adequately describe them to herself.

Brilliant. Now she couldn't even read herself. She felt like blaming Bruce for that, but that was more than slightly petulant.

Mentally shaking herself, she tuned into Fury. It wasn't as easy as it usually was. Tony and Bruce's interactions were more than distracting. Each time Tony spoke up, Bruce would watch him with something akin to adoration. And not the blank adoring stares she saw from the numerous ditzy blondes, wannabe geniuses and sleazy businessmen that followed him around at galas. No, this was completely different, coming from a deep admiration and not a shallow infatuation.

She recognised their relationship had obviously developed leaps and bounds, but couldn't put a word on it. It was more than frustrating.

'All I'm saying is, if you don't want to be hacked, up your security,' Tony was saying while nonchalantly brushing dirt off his Armani jacket that wasn't even there.

It was amazing the feelings Fury could convey without so much as changing a muscle in his face. The aura coming off him was very clear though. Tony must be on top form today if he was actually starting to make Fury break.

'We have the best in the business, Stark,' he said in what appeared to be a calm tone.

Tony simply did that thing where he gave a look that clearly conveyed he thought whoever he was looking at was an idiot. Then he went back to dusting his jacket.

Fury hardly bit back a sigh and started to sip his hot coffee rather quickly.

'Wait,' Steve said slowly, the way he did when he wanted to make doubly sure he knew what he was saying made sense in this modern world, 'don't you work for SHIELD as a consultant, Tony? Why can't you help them on their,' here he paused, glancing at Clint,' software?' At Clint's affirmative nod, he reiterated confidently, 'Software.'

Tony turned his 'You're an idiot' expression onto Steve, but Natasha noted that it didn't have as much force as it did when directed at Fury. 'I was a consultant on the Avengers project. That didn't include doing work on the shields,' here, he couldn't resist sending a grin over at Bruce, who returned it with a pained grimace that somehow looked amused at the tortured pun, 'that protect all the secrets on the Jolly Roger.'

Clint laughed outright again, purposefully ignoring the warning glance from Fury.

'Rogers does not look jolly,' Thor said with a tilt of his head, pointing at Steve.

There was a brief pause before both Tony and Clint broke down, Clint even thumping the table. Bruce was silently chuckling, eyes closed again, head down, like he didn't want anyone to see he was laughing. Natasha couldn't help but smile as well as Fury actually closed his one eye for a brief moment, like he was praying for patience. She was getting to like this group.

Even Steve was now smiling, albeit unsurely. 'I think he was referring to something else, Thor,' he said gently. He glanced at Clint again.

Clint nodded vigorously, unable to speak because he was gasping so hard, grey eyes bright in a way they hadn't been since the Chitauri.

Natasha decided she was really getting to like this group if they could bring that out in Clint so quickly.

Tony was grinning madly then glanced over at Bruce. For some reason, it wavered.

Fury started to talk amongst the dissipating chuckles, slowly and deliberating, 'Do you think you could expand your duties for three months to help us upgrade the Helicarrier's software?'

He began to sip his coffee again like it was his elixir for dealing with Stark.

Tony's grin suddenly took on a slightly vindictive glow. 'Me and Brucie could,' he said. With that, he slapped a hand down so hard on the other man's shoulder that it made him give a startled, 'Ooph.'

Fury actually snorted the coffee.

Thor looked disturbingly excited like he couldn't wait to battle the Hulk again. Natasha crouched low, ready to spring back and let fly. Clint was pretty much identical.

Steve looked frozen, but his blue eyes were calculating until a realisation dawned on his youthful face.

'What the hell, Stark!' Fury growled, hand firmly on his gun.

Natasha saw all this while still watching Bruce. He looked mildly surprised to see all their stances. His body slumped deep into his chair, as non-threatening as possible. His eyes, strongly brown, briefly caught hers. For once, she was able to read his emotion.

Hurt.

Tony's smile turned downright vicious. 'What?' He tried for innocence, but the bite in that one word was practically venomous.

Fury didn't say a word, but simply glowered at the much smaller man.

Tony didn't back down. The man never did. It was something that got him into so many dangerous positions, but it was also the way he survived them too. 'Would you care to elaborate your problem, Nick?'

Fury's eye flicked to Bruce. The physicist was almost curled into his chair, hands now fiddling together. Now, Natasha recognised him well. That thought made something in her chest constrict.

Tony followed Fury's gaze. His expression became murderous.

He jumped to his feet and looked ready to storm right up to the master spy. Natasha's eyes couldn't help but widen. That was either extremely brave or entirely insane. Tony appeared to be the expert of walking that line.

However, before he could, a gentle hand grabbed his sleeve and tugged insistently on it. Tony didn't tear away from the touch, as everyone surely expected him to, but instead, paused in his path. His stormy eyes wouldn't leave Fury's.

The tugging took on a more urgent pull.

It was visible when Tony decided to heed. A sigh filled his entire body and escaped in a large whoosh. His eyelids closed briefly then opened.

Chestnut brown met honeyed brown, one suddenly gentle while the other was extremely worried, with still no hint of green. They stayed like that for a moment.

Tony sighed again, large and exhausted. Running a hand through his untamed black hair, making it slightly crazier, a smirk pulled at the corner of his mouth, small, but genuine.

'All right, bud.'

If Natasha hadn't seen his lips move, she would have sworn that wasn't Tony's voice. It was unlike she had ever heard him speak before. So soft, gentle and … un-Tony.

Without another word, he grabbed Bruce's arm as he uncurled and slunk off the chair. Tony slung an arm around the shorter man's shoulders, tossed a poisonous look over his shoulder at Fury then marched out better than any diva could because he somehow made it look classy rather than throwing a tantrum. Bruce just remained tucked under his arm, head bowed.

It was that which made Natasha relax back. Not because she felt threatened, but because how could one threaten someone that looked so scared and helpless? She knew Bruce was anything but the last word. Seeing him tucked against Tony like that though … she had no choice but to see him as something that needed to be protected.

She felt a jolt of … actual guilt … when she realised she was a part of what made him curl in on himself like that.

What the hell was Bruce's presence doing to her?

Before she could think further, Steve was up and out of his seat, following the two men out of the room without even a word.

Everyone sat in silence, unsure how to pick up after all that.

Finally, it was Clint who turned to her, grey eyes blinking widely. 'Damn. I did not see that one coming.'

Whether he was referring to the way Tony and Bruce reacted to each other, Bruce not 'Hulking out', Tony looking like he was about to eviscerate Fury, Tony all of a sudden taking on a persona unlike anyone had ever seen on him before or Steve following them out or … or … any other crazy thing here today, Natasha had no idea.

Whichever one it was though, she agreed with them all and nodded, suddenly not feeling like talking.

At the head of the table, Fury was leaning his knuckles on the surface, breathing heavily. It wasn't from anger, for that Natasha was sure. More exhaustion.

Thor sat up in his chair, smiling around at all of them, obviously trying to put them at ease. 'I did not know that pie had numbers within it,' he said conversationally. 'How is that so?'

Clint's smirk returned. 'Please ask Stark that next time you see him.'

Natasha glanced at the door. One thing was for sure. Neither he nor Bruce were coming back in this room today.

She had no idea why she found that idea disappointing.

This was Natasha's first time noticing Tony and Bruce's different interactions with each other without being able to name what exactly it was.