"I've... I've never done this before." The super soldier, normally so bold and unphased even in the face of almost certain death, admitted with a stammer, as the naked scientist straddling his lap kissed his neck. Bruce pulled back when he heard the words, eyes wide. He'd heard that the mighty Captain America had been quite a celebrity in his day, and he'd assumed that Cap had been with someone else before, even if it wasn't another man, as it was now. Still, he didn't comment on it. Steve was clearly already embarrassed, he didn't need to make it worse.
"It's okay. Everyone has to have a first time." He murmured softly, in his usual calm voice. Steve nodded in agreement, a little nonsensically. Bruce went back to what he'd been doing a moment prior, but slower, softer, and kept his hands off Steve's shirt buttons, instead resting them on his shoulders. Steve groaned slightly as he felt Bruce's teeth gently worry the sensitive skin on his neck.
"We wont do anything you don't want to do. I like this. We don't have to go any further." Bruce reminded him. Steve shook his head.
"No, I want to, I'm just.." He seemed at a loss for words.
"Scared?" Bruce supplied. Steve nodded.
"I'm scared I'll hurt you." He confessed after a moment. Bruce was taken aback. Well that was a first.
"Because of the serum? You think you're too strong?" Bruce asked.
"When I first became a super soldier, I ripped a car door off by accident. I've gotten used to it since then, but I've never done this before. I'm worried I'll get caught up in the heat of the moment and forget what I'm doing. I don't want to hurt you." He explained, looking tenderly into the eyes of his lover. Bruce smiled at his affection.
"I know the feeling. But if that was the only problem, why not just let me top, the first time? I can keep you under control that way." He asked.
"That didn't occur to me. Yes, it's a good idea." He stated a little formally, before trying his hand at a sultry grin, "Yeah, fuck me, Bruce."
Bruce snickered, before going back to Cap's shirt buttons, this time undoing them all and tugging the garment from his body, revealing Cap's perfectly chiseled chest. Bruce gently pushed on Steve's shoulders until Steve took the hint and laid down. He then grasped Steve's wrists, and pinned them down above his head, before giving some much-needed attention to Cap's torso, ravaging him with his tongue and lips until Cap moaned with both pleasure and frustration.
"Bruce~!" He groaned, bucking his hips up slightly, his rock hard cock searching for friction. Bruce felt it, and grinned. He slid from his perch into the spot between Steve's legs. He decided to tease Steve, palming the bulge through the thick denim of his jeans before he unbuttoned them, and pulled down the zip with his teeth. Steve groaned as he watched him, his worries already forgotten. In a second, Bruce had pulled away Steve's jeans and briefs, and was admiring Steve's "mini soldier", as Tony insisted on calling it. Though there wasn't anything mini about it. Steve's muscles hadn't been the only things to grow because of the serum. Bruce was suddenly glad he wasn't bottoming. Still, that didn't stop him from taking it into his mouth. As with before, he teasing, at first only licking the slit, lapping up the drops of pre-cum that were already there. Steve shivered, biting his bottom lip and closing his eyes as Bruce began to circle his tongue round and round the head, and just as he thought Bruce was going to move further down, he pulled away. Steve's groan of frustration turned into a startled moan of pleasure as Bruce did other things with his tongue, things he had not even heard of before. Bruce began to kiss where he would later fuck, with the same enthusiasm and vigor as he had done to Steve's mouth earlier. As he did so, Bruce fondled Steve's balls, massaging them with his fingers. Without warning, Bruce pulled his tongue out of Steve, and sat up slightly, moving so that he could go down on him. He tried to take it all, bobbing his head, taking more and more each time. Steve moaned, bucking his hips up in time to meet Bruce, careful not to choke him. Soon Bruce was deep throating him, so every time he swallowed Steve could feel it, and hissed. And then Bruce started humming. With a cry, he came down Bruce's throat. Bruce swallowed it eagerly, licking his lips to make sure he swallowed every drop of his lover's seed. Steve was laid there panting, in that post-orgasm bliss, when Bruce descended on him again, licking at him until he was hard and throbbing again, before pulling away.
"Roll over," He commanded. Steve did so eagerly, shakily pushing himself up onto all fours. Bruce coated his fingers with lube, and pushed into Steve's tight ass. Slowly, so as not to hurt him, before pulling it out again. Then he began thrusting, gradually picking up speed, and when Steve moaned, Bruce added another. He scissored his fingers, before adding a third. Soon, Steve was begging for Bruce to fuck him properly.
"Please, oh God, please. Bruce! Please, fuck me, take me, mark me as your own, please God fuck me!" A litany of gasps and moans fell from his lips and Bruce smirked. Pulling on a condom, and coating his cock with the same lube he'd applied to his hands, he thrust into his writhing lover. Steve groaned, stiffening a little but beginning to rock back into the thrusts as he became more accustomed to them.
"Ngh! Faster!" He cried, and Bruce began to pick up the pace. Snapping his hips back and forth, his hands dug into Steve's hips, hard enough to leave bruises, but that only seemed to increase Steve's pleasure.
"Ah, Bruce, I, Ngh!" His sentences became fragmented and jarred, punctuated by moans and gasps. Bruce began to pant in between his moans, but too late did he realise that. He realised too late that his heart rate was rising. That he was going to Hulk out. He tried to pull out of Steve before he did, but as the sensation of changing ran through him, he balled his hands into fists, clinging tighter still onto Steve's hips. He closed his eyes, as his body hunched over Steve's, and as his skin rippled, muscles straining and veins bulging, he changed. His skin faded from tan to a violent hue of green, and his size doubled. He screamed, letting out the fury that came from being the Hulk. Steve screams of equal parts pleasure, pain, and fear that he was going to be ripped in two intermingled with Bruce's.
Hulk opened eyes. Small blonde man underneath Hulk. Part of Hulk inside of attractive blonde man. Hulk try to remove small blonde man by hand. Small blonde man make noises. Hulk try to pull self out. Hulk stuck. Try push back in, then out again. Nghh. Hulk like that feel. Do again. Nghh! Hulk like. Small blonde man make noises. Hulk think small blonde man like. Hulk do again. Hulk do again faster. Nghh! Hulk continue to do. Small blonde man moves arm. Move back and forth underneath him. Hulk think man rubbing his belly. Hulk not care. Hulk like~. Hulk out of breath. Hulk need faster. Hulk almost there. Hulk moan. Something happen Hulk! Feel good~~. Hulk pull out properly. Small blond man not move legs. Hulk pick small blonde man up. Small blonde man dripping green. Hulk groom man. Lick green off. Small blonde man moan. Squirts white on Hulk hand. Hulk taste white. Salty. Hulk hold small blonde man. Sleep.