Work Text:
The thing about Bucky’s version of the super serum was that it wasn’t perfect. Sure, it was good, he was well and truly enhanced, but it was… well, it could sometimes be a bit backwards. So, while Bucky’s serum was generally far more efficient and powerful in carrying out its various functions, the functions themselves meant that his serum could be a real pain in the ass sometimes.
At this particular moment, Bucky had been woken up by a nightmare and was now achingly hard in his pants. This wasn’t unusual but it was certainly uncomfortable. Bucky knew it wouldn’t go away until he either cheered up or dealt with it and since he was shaking still from the latent terror and adrenaline of his nightmare, he knew he wasn’t going to be out of this funk anytime soon. That would all be manageable, if not for the fact that Bucky could hear footsteps approaching from down the hall.
Bucky was lying on his back when the door opened. Though he kept his eyes closed, he knew there was no way in hell he was fooling Tony.
“Can’t sleep?”
Bucky shrugged. Since he was lying down, it probably looked like he was just twitching.
“Bad night?”
Bucky made the shrugging motion again. “Bad is a bit of an understatement.”
Tony slipped under the covers. “Wanna talk about it?”
“Nah.” Bucky rolled over, intending to put his arm around Tony, but what really happened was his sensitive cock ground slightly against the bed and he made a choked sound.
Tony went very still. “Well,” he purred, “I didn’t know it was that kind of bad-”
“Tony- no- please don’t,” Bucky interrupted. “It’s not like that. It’s… I can’t control it.” He bit his lip, frustrated at his inability to find the right words.
“No one can control it, that’s where the term ‘inconvenient boner’ comes from.”
“No!”
Tony rolled over to face Bucky. “Hey,” he murmured softly, you want to tell me what’s going on in that head of yours?”
“It’s… it just happens. Every nightmare. Every time I’m missing Steve. Whenever I’m worried about you.”
“Uh… wow, okay, I’ll admit I didn’t peg you as the sort of person who would find negativity arousing but kinks don’t always make sense.”
Bucky felt a flare of gratefulness and wonder that Tony would accept him so quickly, even if that wasn’t what was happening. “I don’t find that arousing. It’s- the serum does it. It was among my records from HYDRA, just a footnote.”
Tony was silent for a long moment and Bucky feared he was either doubting Bucky’s words or had just fallen asleep.
“Tony?”
“Hmm? Oh. Sorry- I just can’t help but think that must be uncomfortable for you, that’s all.”
“Well… yeah… the serum makes it its business to keep me ready whenever I’m feeling down. It’s supposed to counteract the negative emotions.”
Tony hummed, “Yeah, coming releases all those fun, positive chemicals in your brain. That’s just… screwed up. Every time I think I’ve learned the lowest HYDRA can sink….”
“They never- uh, used it against me. If you were wondering. They never raped me.”
Tony just hugged Bucky. “Any way I can help, you’ve got it.”
Bucky tugged Tony closer, “Just stay right here, like this.”
----------
It was sometime in the early hours in the morning when Bucky finally gave up on trying to sleep. Huffing to himself, he slipped out of the bed, careful not to disturb Tony, and headed into the bathroom. After spending a few hours hard, his already over-sensitive dick was starting to hurt. At first, it’d been the normal ache that came with need he’d felt, but by now, he was honestly feeling a little raw. From lying in a bed. Jesus Christ, he needed help.
Right now, though, he definitely had more important matters to deal with. Namely the reason he was even awake at all right now.
Resisting the urge to punch something, Bucky grabbed his cock and started to stroke. He was on edge enough that he didn’t care to search for lube right this instant, and it would be over fast enough, with the serum would be working well enough, that any discomfort would be small and not last long anyway. Discomfort, that is, other than the reddened, leaking variety already present.
Bucky bit his lip, fighting the urge to groan at the feeling as a deep heat settled deep in his stomach. He teased at the slit and couldn’t prevent the grunt he let out at that, glancing guiltily at the closed door to the bedroom. It wasn’t that he thought he couldn’t (or shouldn’t) jerk off without Tony there, it was just that Bucky was really wishing Tony was there, but the genius needed sleep. It only made him feel worse that he knew Tony wouldn’t mind.
Firmly putting the thoughts out of his mind, Bucky gripped his needy member a little tighter and began the familiar movements. His first orgasm came after only a minute or two- it was a good thing, he thought distantly, that he had gotten up now. He wouldn’t have been able to change the sheets without waking Tony up if he’d had an accident in the bed. Bucky didn’t bother contemplating the observation any further as he felt he hadn’t grown any softer in the wake of his orgasm.
So, it was one of those days, was it?
On the worst days, Bucky could keep coming to the point of literal exhaustion, the serum in his veins refusing to let him rest until either it was satisfied he was no longer unhappy, or he passed out. Of course, Bucky had only gone that far before once, when he’d been fresh on the run from HYDRA and had still been relearning everything about sex and his body. Sometimes, he thought about that, wondered whether he might’ve have woken up enjoying the afterglow if he hadn’t been shaking from paranoia and fear.
But that wasn’t important right now. What was was getting another orgasm or two out before he cleaned up and rejoined Tony, hopefully with enough happy chemicals having been released to let him sleep for at least a few hours. It was never fun, having an instant boner tied to his emotions, Bucky mused as he gripped his dick again, but maybe it was actually a good thing? Like… HYDRA thought the purpose was to cheer him up.
Nope. It definitely wasn’t. Just frustrating.
It did lead to this, though- Bucky’s hand running up and down his straining erection in the middle of the night because the normal sensations of sleeping in a bed were too intense for him to sleep. He was missing sleep, yes, but his senses were always dialled up to eleven when this happened. Everything felt… just a little bit more. His mind went unbidden back to the last time this had happened - to the sensation, especially - of how the slick slide of his lubed hand had felt so good with his increased sensitivity. It was like hyperawareness, he imagined, with how he could take note of every little change in the strength and angle of his grip, how he could almost feel every ridge of his fingers, how he-
The bathroom door opened and Tony stepped through, blinking sluggishly and yawning widely.
They both froze, staring at each other for a moment before Bucky awkwardly smiled, “Let’s face it, this isn’t the worst thing you’ve caught me doing.”
Tony chuckled, “Even our wedding was crazier than catching you jerking off in a bathroom in the middle of the night.”
Bucky shrugged, trying not to look too guilty. “I’m just-”
Before Bucky could continue, Tony help up his hand. “You don’t need to explain. I know you’re aware that I don’t mind if you wake me up so I know you’d have considered it. It’s okay.”
“You should go back to sleep. You need your rest.”
“Mm, yeah, I just needed the,” Tony gestured at the toilet, “conveniences.” He yawned again.
“Right.” Bucky left the room and sat on the bed instead. He knew Tony didn’t care whether he stayed or not but honestly, it felt a little weird to Bucky. He laid back on the bed, idly stroking his cock while he waited for Tony to return.
He should’ve known better.
By the time Tony was finished in the bathroom, Bucky had given in to the urge to start moving again. He rocketed toward completion once again, this time feeling almost no relief at all. He growled in frustration and rolled over to face Tony. “I can’t stop. It just keeps getting worse!”
Tony started to nod but aborted the motion halfway through in favour of rapidly clicking his fingers and opening the closet door. He ducked inside, and Bucky heard the scrape of the door that led to the semi-hidden room where they kept their sex equipment. When Tony emerged, a towel slung over his shoulder, he was triumphantly holding aloft a black dildo. “Now hear me out, Bucky,” he hurried over, “your issue is that every time you finish, the experience fades away and your version of the serum registers the negative emotions or whatever and then you’re hard again, right?”
“That’s about the shape of it, yeah.”
“So, what if it didn’t end.”
Bucky frowned, “…You’ve lost me.”
“Well, you need sleep, right? But your body is pushing you into a loop of coming and needing to come again almost immediately again, which will eventually exhaust you and start all over again when you wake up. So my idea is that, instead of this,” Tony gestured with the dildo at Bucky, “you just sleep with this thing inside of you tonight. We both know you like being fucked so this should provide some pleasure.”
“Hopefully enough to let me rest!” Bucky finished excitedly. “Great idea!” He took the dildo as Tony passed it to him, eagerly watching the other man lube his fingers up. When Tony breached his hole, it wasn’t teasing like normal, mostly just efficient and a little impersonal- designed not to rile Bucky up any further at all. He still groaned at the feeling of Tony stretching him, efficient or not, it was still making him moan and shift restlessly.
Tony tapped the base a few times, cataloguing Bucky’s reactions. “You wanna get off one last time before we go back to sleep?”
“Y-yeah,” Bucky stuttered as Tony shoved the dildo in a little deeper. He rolled his hips a little, encouraged by Tony rocking the toy a little. Tony knew just how to angle it to brush against Bucky’s prostate with just the right amount of pressure. He groaned, fucking himself deeper on it. He kind of wished that Tony had picked a bigger one, but he was certain he wouldn’t be able to sleep later if he had. This one provided just the perfect amount of pressure and sensation for Bucky right now.
He grunted when Tony spread his legs a little wider and wrapped his hand around Bucky’s cock. The genius dug his thumb in slightly just under the head of it, knowing the proximity to the nerve endings would drive Bucky mad if it wasn’t followed with any touches to the head. And it did.
“Please Tony, don’t tease,” he whimpered.
Tony mock-huffed, relenting, “I guess it is late, isn’t it?”
Bucky nodded quickly.
“Maybe you’d rather not come tonight? Just sleep instead?”
Bucky whined, “Tonyyyyy-”
In response, Tony just shoved the dildo in further and pulled on Bucky’s balls. Bucky thrashed, his back arching off the bed as Tony was relentless, playing with them in time with the thrusts from the toy. Bucky came with a cry, pleasure whiting out his vision. He shook as he came down from the high, moaning from the aftershocks. His body was lax and he yawned, suddenly, finally tired. Tony used the towel he’d brought earlier to wipe Bucky down, then settled into the bed himself. Bucky smiled at him, “Come here,” and snuggled close to the other man. With that, he finally drifted off to sleep.