-This is the Tony/Bruce portion, the second half, and Steve/Tony portion will come eventually...-

Within the shiny walls of SHIELD's heli-ship, the laboratory designated for Mr. Stark and Mr. Banner bustled. Monitors of various sizes and positions beeped and whined while the two scientists busily evaluated their readings. Sourcing the small waves of gamma was going to be a rougher task than first imagined.

Tony leaned back and rubbed his chin as the numbers on his transparent screen sky rocketed into decimal points even he was weary of. He stretched his arms backward and made a loud, overly dramatic groan. He looked over to Bruce for a reaction—there was none.

"Well, it seems that time is of the essence in this gamma matter…" Still silence, "Oh, speaking of time. It's about 3:30." Tony headed over, leaned, and stared at Bruce through the screen, "In the morning!" He added with a bit more emphasis. Merely looking up through his glasses at Tony for a moment, Bruce silently went back to his data collection on Loki's scepter. Mr. Stark stood hovering over Bruce for a few seconds; the monitors continued their annoying scanning and beeping. Bruce couldn't help but let a small smile cross his lips when he heard Tony's exasperated sigh as he turned on his heel and shot his hands in the air.

"I've never worked this hard…I don't work this hard." Tony complained as he went back to his screen, mindlessly tapping it. Sometime later, at an ungodly hour, the scanner's input steadied and the date collection became productive. The algorithm Bruce initially set up was finally in motion—as was Tony's virus—and it would be a matter of time before the gamma rays could be detected. Bruce let out a relieved sigh and leaned back in his chair. He took off his glasses, eyes weary. He rubbed them gently while making a small groaning sound, like a gamer whose time was up. Little did he know, Tony was intently eyeing this whole display from across the room.

"Well, I sure hope all that pays off soon." Bruce said in a voice that usually be used when talking to oneself.

"And now we play the waiting game." Tony said in a purposely louder voice than Banner's. He watched as Bruce flinched ever so slightly at his volume, studying his body movements and language. Tony smirked; he stood up quickly and swiped his arm across one of the desks. He sent papers and random assortments crashing to the ground, the metal on metal clanged loudly within the lab. Once again he saw his newly made lab rat flinch again, but still not the reaction he wanted. Tony lifted his arm to make more ruckus but Bruce's louder than normal voice caught him off guard.

"Do you mind?"

Tony shot a glance towards Bruce who looked a little fatigued. Stark simply shrugged and said nonchalantly, "No, not at all. Go green, buddy. I think letting out a little steam is good once in a while."

Bruce smiled wearily and shook his head. He rubbed his hands nervously out of habit. "You sure like making jokes of pretty serious matters, huh Tony?" He walked slowly over to the rubbish and knelt down, slowly picking up Tony's mess.

"Who jokes? Moi?" Tony questioned, kneeling down to help Bruce. They picked up in silence for a few moments. Bruce felt Tony's eyes burning holes into him, but he never let his gaze lift from the objects being picked up. With his heart pumping a tad too fast for comfort, Bruce shifted his weight to stand only to be held down by Tony's grasp. Bruce looked up quickly, fearing what God awful thing Tony was going to try next. He closed his eyes and began breathing, trying to keep his anger at a safe level.

"Tony," he said with his eyes still closed, hands gripping the papers into a crumple, "stop with the childish attempts at-" Bruce felt the tiny bristle of facial hair press against his skin as Tony's lips pushed roughly into his. The two scientists settled into the kiss for a few moments before letting it heat up. Bruce let Tony's weight push him down onto the metal ground, his bottom made a dull thud as it hit. He felt Tony's lips maneuver his own with uncanny professionalism.

Bruce broke the kiss, pushing Tony away from him sharply. "What the hell are you doing?" He said, his breath barely catching. His heart pounded eerily in his chest as he watched Tony trace his thumb on his bottom lip. Bruce gulped.

Stark stared into his flustered acquaintance's eyes. "Letting out steam." He made the statement as if it was obvious fact, "I find you fascinating."

It was news to Bruce. "This game you're playing may be just 'letting out steam' to you. But I…" All sensible thought trailed off as he watched his fellow scientist oddly got on his hands and knees. Tony crawled towards the very vulnerable Bruce; his deep stare never faltering once. Banner began to retreat, but something strongly stopped him, holding him back. An unnoticed force—although Bruce had a keen idea what it was—kept him still, allowing his predator to straddle him easily. Bruce felt his breathing quicken as Tony's slim figure nestled into his lap; knees on either side of him. The silence of the room seemed to intensify as Tony brought his lips once again to Bruce's. The kiss set fireworks off in Bruce's mind. He felt those slim hips slowly let their weight press against him. God, Tony was good at this. But now wasn't the time to be swept away. This kind of situation would…

"Wait…" Bruce whispered as he parted the kiss.

"Nope." Tony did not miss a beat. His lips, as if pulled by a magnetic force, went straight back to Bruce's. He tilted his head into the kiss, making it deeper, passionate, and heated. Their lips made smacking noises that would otherwise be foreign to the scenery. "What if," he said desperately between kisses, "the 'other guy' says no?"

"I'm very persuasive. He'll come around."

Bruce fumbled beneath Tony's mastery; shifting his legs awkwardly as he felt his body begin to react. It had been too long since this kind of human interaction. As if the billionaire could read minds too, Tony pushed his hips down onto Bruce. The contact that had been absent in Bruce's personal life was easily welcomed. He felt his mind begin to blur a bit, thoughts becoming unclear. Tony rolled his hips smoothly, with some force.

"Tony…this is…a pretty stupid idea…" he breathed in protest, but to no avail. Tony was obviously terribly skilled in this area, and he sure as hell wasn't going to let it stop now. Bruce felt his mind clouding even further. It wouldn't take very long before...

Another roll of the hips, grinding hard, caused a low, deeper than his usual tone, growl come from Bruce. His eyes shot open at the sound.

'No, not you too.' Bruce's thoughts scolded the other guy. He could almost see the big face smiling dumbly.

"Mr. Hulk, I'm flattered." Tony said with a smirk. Bruce lifted his hands to cover his face, this entire situation was too embarrassing, he was definitely going to lose control—especially since the big guy wanted a part of it too. Tony caught them by the wrists. Bruce watched at Tony brought them to his lips, kissing them softly.

"Odd…" he mumbled.

Tony chuckled, "Well, if you insist on acting femininely, I'll treat you like a lady."

Bruce narrowed his eyes and pursed his lips in a pout that Tony found pleasantly adorable. This was originally a joke gone too far, but he slowly found himself enjoying the timid scientist's company. He inwardly gleamed at the little emotions Bruce let out. Tony knew this is a side of Bruce no one has seen before; he loved being a first.

He's always wanted a toy of his own to tease too.

"Follow my lead…" Tony said suddenly. Bruce morphed his lips to speak, but Tony pushed him on the chest a bit roughly. His back fell to the metal floor. Lifting his head up slightly, he watched Tony adjust his straddle. The billionaire's dark lashes barely brushed against high cheek bones as his gaze focused on his actions.

"Woah." Bruce said, astonished. Feeling like even more of an idiot, Bruce watched Tony's piercing, determined eyes finally look up. "Uh…Tony?" In one swift motion, Tony leaned forward and grabbed hold of Bruce's purple shirt. Pulling outward, the buttons flied across the metal floor, scattering like broken glass. "I liked this shirt."

"Do you ever shut up? I said follow my lead." Tony placed his hands on Bruce's revealed skin, his cool hands causing the scientist to breathe in a sharp intake of air through his teeth. Experienced fingers glided along his goosebumped skin, delicately feeling him. Tony brought his lips hard onto Bruce's; his tongue easily gaining access. Bruce grunted into the kiss, quickly matching Tony's speed. He was a fast learner. His hands combed through Tony's hair, gripping it ever so slightly. Suddenly, Bruce felt his arm lose control. It tugged harshly at Tony's hair, pulling his lips away from Bruce's. The billionaire let out a small grunt.

"S-sorry…" Bruce said, for lack of anything better.

Despite that minor setback, the kissing continued. Tony easily took off the rest of Bruce's clothes, along with most of his own. "Lift your hips a tad would ya?" Tony breathed, and Bruce obeyed. Off came the last layer of fabric standing between Tony and his prize. The kisses became farther spread apart as Tony's face left Bruce's. Like dots on a map, the billionaire left tiny kisses as he moved lower. Bruce shot his head back against the metal floor, ignoring the sharp pain his movement brought. He placed his palms flatly on the cold metal, he bit his lip to hold in any more embarrassing noises. Tony's tongue moved easily, he moved his lips over Bruce's extremely hardened, and already wet, member. As if he'd done this before, Tony let most of Bruce into his mouth, the tip slightly touching the far back of the roof of his mouth.

"W-woah!" Bruce sat up and placed his hands on Tony's shoulders. "That's…that's good enough. You don't have to-"

Once again Bruce was at a loss of words as those deep brown eyes looked up through dark lashes. Tony closed his mouth over Bruce, sucking hard. Immediately, almost comically, Bruce went straight back onto the metal floor.

"Shit, Stark…" He mumbled wearily, swinging his forearm over his eyes. Moments passed, Bruce occasionally lifted his head to remind himself that, Yes this was indeed happening. Tony Stark, the Tony Stark was going to town on his lower half.

Bruce felt jolts of pleasure rock his body, he quivered every now and then. His breathing burst through his nostrils. Feeling his climax approaching, Bruce once again planted his palms on the floor—not as easily this time, since his sweat made them pretty slippery. His mouth opened slightly as he just nearly came. That's when the sensation down below stopped. Bruce made an almost disappointed moan as he looked up again to see Tony smiling at him.

"Not yet." Was all he said, and he glided his fingers over his saliva on Bruce. Bruce watched as Tony wet his fingers some more in his mouth. As he pulled them out a trail of saliva connected his lips and index. Without saying anything, Tony held his fingers out of sight. At the sudden pressure, Bruce sat up once again.

"Woah!" He said for the third, annoying time, "No, no nonono." He laughed, "I don't think so Stark." Tony paid no attention, pressing his fingers farther into Bruce. Bruce responded, much to his dismay, with a small moan. All this excitement was good and dandy, but he was close enough to losing it as it was. "Stop." He said, unconvincingly. He heard Tony chuckle, pushing another finger in.

For what seemed much too often during these events, Bruce's mind went into that clouded state. He groaned loudly, his voice low and husky. The groan turned into a mild yell as his felt his arm move on its own, his palm landing harshly upon Tony's left cheek. Bruce's eyes widened, his hand still rested upon Tony.

"Oh my God…" Bruce said, his face warming a bit. "He's into S&M."

Tony took hold of Bruce's hand, sucking on his fingers for a moment.

"That won't be a problem." He said before taking out the instrument used earlier to taunt Bruce's 'other guy.' "I came prepared."

As the night-well, early morning's-events continued. The silent spectator from just outisde the laboratory's doors held himself tighter. "Tony..." he breathed heavily and moved his hand faster to the oblivious scientist's movements, "Oh God, please forgive me."

TO BE CONTINUED...in some weird...attempt at a threesome...kind of way...? maybe... I don't know.