Dinner passed quietly.
When they were done, Tony retreated back to the workshop and began working on re-naming the NanoKink. After several crossed out scribbles of things like Pulse-Identifier, BannerScanner and Pulce, Tony sighed and threw down his pen, pinching the bridge of his nose and screwing his eyes shut.
Damn he needed coffee.
"Knock knock."
The engineer looked up to see Bruce stood behind the glass door into his workshop. The locked glass door.
Tony stood and made his way over to it, the doctor watching him as he did.
After a few seconds of silence between them, Tony inclined an eyebrow. "Yes?"
Bruce frowned for second. "Well can I come in?"
"Oh, right." Tony waved a hand in realisation. "You need to return that wristlet." He ordered JARVIS to unlock to door as he turned his back on the doctor to return to his bench.
"Actually, no. I came to...agree to do it."
With his back to Bruce, Tony raised both eyebrows now as he pretended to be busy polishing the main device of the NanoKink.
"Oh?" He swivelled on his chair to face the man.
The doctor simply nodded, now stood just inside the doorway.
"I understand that you have checks to do and an invention to complete so I'll...I agree to take part. To help you."
"That's incredibly chivalrous of you, Bruce. I don't know what to say-"
"Don't make me regret my decision."
A playful smirk twitched onto Tony's lips and he lifted his hands in defeat.
"Okay, big guy. Sure. I appreciate you agreeing." He stepped closer, inhaling sharply, eyes serious now. "But like I said, I'm gonna need you to trust me. This...experiment...requires a significant amount of physical..." Tony cleared his throat. "Touch."
"Physical touch?" Bruce raised a smirking eyebrow. "What are you doing with me?"
"Nothing major." The engineer waved it off. "Just things that I may need your permission for. We should probably use some sort of system. Like traffic lights, or hot and cold."
Bruce contemplated the idea for a second.
"So, you're testing to see what raises my pulse, in order to-"
"In order to see whether it's heightened heart rate in general that causes you to hulk out, or whether it's strictly limited to anger. It's something I've wondered about for a while now."
Bruce nodded along to show he understood, his hand absently twisting the metal on his wrist.
"So, obviously I'll need your complete and utter trust."
"Wait, just how far will you go with this?"
"That's where the system comes in. You don't like something, or feel uncomfortable, you poke me with a stick and I stop."
"I'd rather just have a safe word."
Tony physically faltered at the use of the term falling from Bruce's lips.
"Okay. So, what do you wanna use?" He asked and Bruce pondered for a moment. Tony couldn't help but admire the tight little frown lines in the doctor's forehead, and the pulsing clench of his jaw when he swallowed.
"I think we should go with simply 'okay' and 'stop'."
"Awesome. And I'll keep checking throughout, yes?"
"Yes."
"And Bruce, I will keep checking. I promise."
Bruce nodded. "Yeah, Tony. I trust you."
"You trust me? Completely?" Tony tested. He wanted to be sure he wasn't taking Bruce anywhere he didn't want to go.
The answer that came warmed the engineer beneath his arc reactor and he beamed an affectionate smile as the words left Bruce's lips.
"Entirely."
"Okay, you ready?"
They were back in the living room. The NanoKink tucked away in Tony's pocket, his own wristlet bleeping rhythmically as it repeated the reading of Bruce's pulse out loud.
Bleep. Bleep. Bleep. Bleep.
"Yeah." Bruce nodded.
Tony lifted the doctor's wrist to line the bracelets up, double checking the configuration one last time.
"Everything okay?" Bruce asked quietly.
"Yep. Everything's awesome." He dropped Bruce's wrist and met his eyes with a smile.
"So. Let's not string it out any longer." Tony clapped his hands and gestured for Bruce to sit. "But I do need to know that I am someone you can completely trust. In order for this experiment to work and get the best results, I'll need to try as many different things as I can."
Bruce nodded.
"But obviously, like we said, you say stop - I stop."
Bruce nodded again.
Tony sat beside him and placed his hand over the doctor's linked ones. "Hey big guy, don't be nervous. It's me." Tony stroked a thumb soothingly over Bruce's skin and the engineer's wristlets began to beep the tiniest bit faster. Tony frowned.
"You know what? Let's change bleeping to some sort of vibration indicator. That noise is gonna drive me nuts." He lifted his hands from Bruce's and twisted the metal open to tap at a tiny holographic screen on the inner side. "There."
"We'll start gradual." Tony returned his attention to Bruce and replaced his hands back over the doctor's in his lap.
"I'd...prefer it if you didn't narrate." Bruce interjected. "Only, it makes it weirder."
Tony lifted his hands, closing his eyes in innocence. "No problem, big guy. I'll zip."
The ministrations started slowly. The pad of Tony's thumbs rubbing gentle circles over the backs of Bruce's hands.
"Okay?" Tony tested.
Bruce nodded. "Okay."
The vibrations from the pulse reader were steady, so Tony moved up a step. He lifted Bruce's hands and simply held one against his cheek. His goatee tickled Bruce's wrist and the doctor stifled a smile.
"Okay?"
"Okay, Tony. Remember I've touched your face before."
"Yeah, but that was different. I want to be sure you're alright."
"I'm fine, Tony." Bruce insisted, and, given that his pulse remained steady, Tony moved up another step.
Moving his head to the side, he pressed his lips once against Bruce's wrist. Not a kiss, just a press. He felt Bruce's pulse kick up a notch.
"Okay?" Tony asked. "No green vision?"
Bruce swallowed and nodded. "Nope. I'm okay."
"Good." Tony smiled before pressing his lips there again and this time dragging them further along Bruce's arm softly. The pulse reader began to speed up ever-so-slightly, but Tony didn't want to keep asking after every little change in movement. So he remained quiet this time. Next, he gently dropped Bruce's hands back down and scooted closer on the sofa. Bruce didn't back up, but Tony felt his pulse jump a little. Boy was he glad he'd switched out the beeping.
The engineer reached to link his fingers through Bruce's, waiting for the pulse to jump again, but no jump came. He smiled at the brunette and the brunette returned it.
"Okay." Bruce answered an unspoken question and Tony nodded in recognition.
Slowly, Tony lifted his other hand up to cradle one side of Bruce's neck. The doctor's eyes fluttered momentarily and his pulse jumped again, but he made no sound for Tony to stop. Gently, the engineer stroked his fingertip up and down the base of Bruce's skull, playing loosely with his hair as he did. Still the doctor made no noise of protest.
Tony paused for a moment, aware that his next move could cause both a jump in Bruce's pulse and potential awkwardness between them should Bruce ask him to stop.
Hesitantly, he leaned closer and, using his hand to tilt Bruce's head lightly, pressed his lips scarcely against the skin under Bruce's jaw.
A sharp intake caused Tony to halt, unmoving; but still Bruce didn't say to stop. His pulse had quickened sharply and Tony could feel it thrum against his leg where the device lay in his pocket.
Slowly parting his lips, he pressed them firmer against the soft skin below Bruce's jawbone and when no further intake of breath occurred, flicked out his tongue just once.
"Tony..."
The engineer pulled back sharply, still cradling Bruce's head but now more for reassurance than for the experiment. "Stop?" He asked, searching Bruce's eyes for any hint of green.
"...No." Bruce replied, and all Tony could see behind dark lashes was blown pupils. "No, don't."
Tony swallowed, diverting his eyes. He never for one second considered what this experiment would do to him too. "Okay?"
"Okay." Bruce's reply was breathy and Tony swallowed again.
Deciding that he could chance it further, Tony mentally prepared himself for his next movement. If anger wasn't the only thing that could bring on the Hulk, this next move would undoubtedly cause destruction to his living room.
Without warning this time, he leaned forward and brushed his bottom lip lightly against Bruce's own.
Bruce mewled. Never had Tony ever thought Bruce would, could, mewl. He flicked is eyes up to check the doctor's for green, but found that they had drifted closed.
So Tony went with 'to hell with it' and captured Bruce's mouth fully with his own. The doctor responded with a light whimper and his hand tightening around Tony's where they lay still interlocked. This had never happened before. None of it. Tony began wishing the experiment was over so that he could just continue however he wished, yet Bruce's comfort stopped him and he slowly pulled back.
"Okay?" He checked, slightly breathless, his own pulse matching that of the doctor's. The device in his pocket was alive and he briefly considered taking it out. But he couldn't disregard the experiment. That would mean Bruce was entirely unprotected. Worst of all, it would mean the things happening between them were for no other reason that the blatant desire for their occurrence. Tony didn't know if he could admit to that sort of thing just yet.
"Tony." Bruce breathed, aware that he wasn't acting himself at all. His eyes were still closed but he spoke to the engineer regardless of the fact he couldn't see him. "Is the experiment over yet? I think we've concluded that the Other Guy only appears when I'm angry."
"Well, not quite Brucie." Tony stifled his sigh of annoyance when the device slowly began to slow it's thrums as Bruce calmed down. "We haven't reached quite where we needed to be-"
"Then take off these fucking bracelets and we'll deal with that when we get there." Bruce sounded frustrated. Worse than that, sexually frustrated and Tony nearly felt his ego inflate that the big guy was so undone by merely one, albeit lousy, kiss.
The engineer grinned, lifting a hand to raise Bruce's chin and forcing the doctor to open his eyes and look at him. His pupils were still dilated and Tony deduced that it was all due to overpowering lust. He swallowed.
"You sure?"
"I knew it was just an excuse, Tony. What do you take me for?" Bruce smirked despite his haze and Tony grinned wider.
"Well, great. Now I feel like a horny teenager caught in the act. You knew the whole time?"
Bruce nodded, amusement dancing in his eyes. "I must give you credit for keeping it up though, especially when I moaned your name. I half expected you to ditch straight away."
Tony feigned a look of mock hurt and Bruce laughed heartily, a sound Tony could get used to hearing.
"Right, okay." He nodded and paused a moment.
"Okay." Bruce added and smiled. "Shall we take these off then?" He lifted his wristlet and unclipped it.
After both were removed and the main device switched off and sat on the coffee table, Tony turned back to the doctor.
"Now, is this definitely-?"
"Shut up." Bruce interrupted.
"No, cause if you do start to-"
"Tony. Shut up." He warned and accentuated the sincerity of his intent by gripping Tony's head with both hands.
Tony paused, his eyes flicking to Bruce's lips. "Make me."
And Bruce did. Well, kind of.