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After months of sometimes agonizingly awkward conversations and rooftop make out sessions, they are finally here. Bruce in a tight workout shirt and thin sweatpants, Clark in jeans and a flannel, standing inches apart in Bruce’s bedroom.
Bruce has had dozens of partners, he’s the king of foreplay, so he starts with the classics. He nibbles at Clark’s jaw, the tendon in his neck, runs hands over arms and back and chest, and Clark seems nearly immune to it all. He’s into the kiss, clearly, but nothing Bruce does to turn up the heat is making a dent. So he breaks out the big guns.
“How do I make you feel good?” When a lover is hard to crack, he simply asks for the key. It makes them flush, usually, and Clark is no different. Being asked what you like in bed can be confronting, but he’s perfected the tone, excited and a little desperate to please, expression open and body language engaged.
“I-I don't know,” Superman never stutters, but Clark Kent is entirely flustered. “I’ve never…”
The part of his mind that loves a challenge clicks on, while the little Brucie voice he keeps on mute is putting up streamers and donning a party hat.
“That’s okay, how do you make yourself feel good? How do you touch yourself when you’re unbearably turned on?” He recognizes that his demeanor and voice have tipped over from darling won’t you tell me and into World’s Greatest Detective, but he can see that the change has - if anything - made Clark more red. Interesting, he likes being the center of attention. Something to consider for later.
“My anatomy doesn't allow for... Self-relief. Kryptonians just don't really do that? Sexuality is for bonding and mating, you're meant to do it with others.”
Bruce feels his mouth flood, wanting so badly he’d be drooling for it if he didn’t have such rigid self-control. He swallows, aware that Clark is probably monitoring the movement as well as his elevated heart rate.
“I see. And you couldn't do that with anybody else because…”
Clark reaches out for his hand, cupping it gently in his and slowly brings it towards himself.
“It will be… easier… if you feel. May I?” Bruce nods, curiosity bubbling frantically as Clark brings his palm to press flat against his own pubic bone. Flat. Because there’s nothing there to block except for a featureless expanse of skin, perhaps hair, he can’t tell through the denim.
“That's not human,” Clark says flatly, letting go of Bruce’s hand but not moving it away from himself.
“Ah. How- no, I don’t need to know that. Is it-”
Bruce pauses, trying to figure out which questions he’d be able to ask without offending, then he looks back up to Clark, who looks relieved.
“You want to figure it out with me?” Clark’s voice is small, hopeful. Bruce nods, hoping his earnestness is clear enough. “Probably easier if I start with what I know then, and we can go from there?”
“Please, and… can I see?”
“Let’s uh, let's finish talking and if you’re still interested, we can see about removing my pants.”
As if anything Clark says would make him turn back from getting to sleep with the love of his life with the added bonus of a Mystery to solve.
“Ma and Pa Kent knew I was male because of the basic information card that was with me in the pod. It said I was a Kryptonian male, what I needed for sustenance as an infant, and a few other facts they needed to keep me alive until I could talk for myself. After that, we figured it out as we went.”
Bruce’s hands itch with want for that little fact card, but he mentally sets it aside to keep listening.
“Most of my bodily functions are similar to the human female structure, minus anything to do with reproduction. When I was old enough, I got access to the Fortress and gathered a little more information, but it’s all academic, full of words I have no definition for and references for which I have no context. I know that reproduction was possible between any two or more of my people regardless of sex, and commonly intercourse was a way of unifying military regiments or settling political disputes. Sex was incredibly common and casual as far as I can gather, but I have found absolutely no reference to…”
“Masturbation.”
“Yes, that.”
“But you do have a drive? And based on the common nature of sex used as bonding, it’s probably fairly high?”
“Extremely.”
“But nothing you’re done so far has allowed you any relief?”
Clark just shakes his head, stepping back from Bruce's touch to sit on the edge of the bed and rest his head in his hands. Bruce has gone long stretches without sex before, or even masturbation, but to have the drive but no ability for decades ? It cannot stand.
Bruce kneels between Clark’s knees, replacing the hands covering his face with his own, cupping his jaw instead. He waits for Clark to open his eyes again, feels the heat of flushed skin and the puffs of air between them.
“Can I see you? Can I try?”
Clark still doesn’t respond, but leans forwards and claims Bruce's mouth again, just as passionate as always, just as perfect. He sits back, drawing Bruce with him, up and over himself until they are laying together with their calves still hanging off the bed but everything else pressed flush.
They kiss slowly and deeply, and eventually hands begin to remove articles of clothing until it's skin on skin, and already Clark is feeling closer than he's ever felt. Bruce draws back, going to his knees again between Clark's spread thighs. Clark goes up on his elbows to watch whatever Bruce is able to manage. If nothing else, he wants to watch him try.
Bruce looks up once with a question on his face and at Clark's nod he begins to use his hands to explore. He runs palms over thighs covered in thick hair, dragging his right closer and closer to Clark's core, leaving his left there as a steady presence. Clark feels fingers and the scraping of dull nails, but the area between his legs is almost the same as the skin between his shoulders. It’s nice, but there’s no extra sensation, no dedicated nerves. After long minutes of uncomfortable silence, Clark starts to laugh, then giggle, and then cackle. He falls back on the bed with his hands covering his face again.
“Clark dearest,” Bruce cuts in, sounding fond, “am I tickling you?” Which unfortunately makes him giggle again.
“No darlin’, but I can see your gears turning, and as cute as it is, I would actually love to be a part of the thought process. Would you mind thinking out loud for me?”
“Of course,” Bruce resumes his studies, this time with running commentary. “The visual appearance is similar to a human female, as stated, minus any explicitly reproductive features, namely labia or clitoris. Tactile stimulation garners minimal response, but does show a small opening a few inches above the anus. Presumably this functions as the urethral opening, but could be something similar to a cloaca. Gentle prodding of the area does not give the expected yielding of an orifice, some external stimulus must be required, or perhaps lubrication…”
“Bruce, do you really think I never tried ‘get it wet and poke it’?”
It’s Bruce’s turn to flush, obviously he would have tried the common solutions, he pulls himself out of detective mode and tries to consider not just the anatomy, but the social and evolutionary aspects.
“Okay, let's start from scratch,” Bruce offers, climbing fully on the bed and pulling Clark back into his arms. “You said the texts were academic, did they have anything on courting rituals or perhaps what would be disqualifying from intercourse eligibility?”
“Let’s see,” Clark tries to remember exact wording, “ mating can be initiated when all parties are in agreement and from distant enough groups. It is proper when seeking to reproduce that such intent is stated before proceedings begin, incubation of offspring will not occur unless all parties choose one carrier and submit genetic material for approval .”
“I see what you mean,” Bruce says with frustration, but his body is loose and he’s running gentle fingers through Clark’s curls. “What does that mean to you, with what you’ve gleaned from their society?”
“They were very concerned with keeping diversity in the population, so siblings from the same pairing were exceedingly rare, and the technology was far advanced from what is here on Earth, so I presume that they used it to find the most advantageous pairings. If you wanted to reproduce with someone specific, you had to meet a threshold for diversity. And then when mating occurred, that was augmented by an incubator. Probably something akin to what is used for premature births here, the young were born quite small to avoid the risks of full term birth. There’s a lot on gene diversity in the population, but basically nothing on how to actually mate! It must have just been so easy for them, it didn’t even occur to anybody to write it down simply. I don’t understand why it isn’t for me.”
Bruce holds him tighter, the skin on skin helps, he’s still buzzing from unresolved arousal, but knowing Bruce is here with him putting his incredible mind to the task helps.
“Without all that context, I have a hypothesis,” Bruce offers. Clark shifts so he can look at Bruce, see that he’s flushed. “If we remove the technology and the social aspects built around gene diversity, we can look at why those were developed. I wonder if the ‘distant enough groups’ and ‘agreement’ and ‘submitting genetic material for approval’ are all… squishier than they sound.”
“Squishier?”
“Not my best word, but I mean that Kryptonian society tended to… intellectualize. To obfuscate the messy parts and cloak anything personal in science.”
“Fair, I didn’t consider there being a level of allusion. What do you think it could mean?”
“I think that the obsession with diversity comes from your body being hardwired not to… engage… with too close of a gene pool match. You physically cannot arouse yourself because you are a perfect genetic match with yourself and thus a terrible candidate for mating.”
“Oh.”
“Yeah.”
“But you’re about as distant a match as is physically possible! You’re a totally different species!”
“Right, so we need to figure out how to submit my genetic material for approval. Kissing isn’t sufficient, clearly, nor is skin to skin contact, but both do seem to be having an effect on you mentally?”
“Very much so, but not physically.”
“So, I’m wondering if perhaps direct application is required?”
“More direct than kissing? I don’t think forcing any kind of insertion makes sense, plus if everybody had similar external anatomy, it wouldn’t be possible.”
“Of course, so we look at what genetic material would be easily shared from your body in its natural state. I’d like to test a theory, if you’ll permit me?”
Clark nods, reluctantly letting Bruce slip from his hold, letting him slide back down to settle on the bed between his thighs once more, again touching and holding and nudging at his skin and finding no quarter. Just as Clark is going to speak up, tell him the teasing is too much, Bruce bends forward and swipes his tongue from bottom to top of his slit. It’s hot and wet, too quick for him to feel the texture, but plenty for him to know it felt good.
Bruce looks up and finds Clark’s shocked expression, doesn’t break eye contact as he puts his mouth back down, lays a handful of kitten licks to the area, just the barest tip of his tongue dipping in. Clark groans and brings his hands up to tug at Bruce’s hair, he’s exceedingly gentle with it, so careful, but also insistent that he not remove his head from where Clark now desperately needs it.
He obliges, gathering more wetness in his mouth he goes back to work, relishing in the sounds he is finally able to pull from Clark, finding that he is quickly opening up. He’s focused on getting Clark soaked and satisfied when he notices something nudging his chin. He pulls back, though Clark whines at the loss, and sees that something is emerging from the slit! His hand finds Clark’s and pulls him to sit up a bit, trying to ignore the way his whole body is pink and his expression pouty.
“Look,” he urges, moving back enough that they can both see what has developed. It’s not unlike a cocoa bean pod, an oblong oval with distinct ridges, some seven inches long and as thick as a soda can in the middle, tapered at base and tip.
“Oh,” Clark says, eyes bright. As much as Bruce wants to, he holds off on touching and lets Clark explore his new anatomy himself first. He watches him reach down, touching with first a fingertip and then when that draws a shaky gasp from himself, gently putting a hand around it. “Oh, Bruce, it’s…”
Clark doesn't last, can’t even finish his sentence before he’s tipped over from worked up to ecstasy. He’s barely touched himself but after so long unable to do even that, it’s more than enough. Bruce watches enraptured as Clark’s muscles tense and fluid pools in the ridges of the phallus, unclear if it came from the tip or was released from the length. After a minute, Clark opens bleary eyes, makes a grabby handed motion towards him and Bruce goes easily. He’s turned on, dick hard and leaking against his abs, but all of that can wait. Their lips meet lazily, it’s probably the most luxurious kiss they’ve shared. There’s no time crunch, no pressing need that they’re trying to meet, just kissing to kiss, connecting and breathing in each other. Eventually Clark pulls back, head lolling to rest on the pillow, peeking down to see the state of himself.
“It’s weird, there’s a weight on my thigh, and it feels like me, feels like that’s mine, but there’s never been a weight before.” Clark shifts his hips experimentally, makes it shift to the other side, leaving a trail of slick as it moves. “I wonder how long it’ll be out.”
“Presumably as long as you and any partner have the mating drive present, but we’ll have to see.”
“What do you mean ‘any partner’, Bruce? It’s you.”
“No,” Bruce says, holding up a hand to forestall any objections. “Of course it’s me, it’s us . For as long as we can have it. But I want to make sure you can have this with others too, in case… I’m human, and we are in a dangerous line of work. There is every chance that there will be another some day, and I want you to have that. And to have it by yourself too! We’ll figure out how to hijack your system to make self pleasure possible, but for right now, I’d like to see how being under a yellow sun impacts your refractory period.”
“We aren’t done talking about this,” Clark warns with a furrowed brow, but doesn’t stop Bruce’s hand as it travels down his stomach towards his new anatomy.
“Yes, dear.”
Bruce takes him in hand, feeling the weight and texture, he’s already gotten further than Clark did himself, dragging his hand over the slick skin, trying to keep consistent pressure over inconsistent widths, dipping his thumb pad between the ridges to see what happens. The skin is dense, but smooth, the whole thing feels heavy in his hand and warm from being inside the body cavity. Clark gets lost in sensation, it feels even better to have someone else touch him than it did to touch himself. He doesn’t notice Bruce moving from laying beside him to kneeling next to him on the bed until the steady grip of his hand is joined by the heat and wetness of his tongue.
He keens, barely keeping from rocketing his hips off the mattress to get more of that , earning a smug look from Bruce. He returns to his task, dragging his tongue up the side of it, collecting the fluids and letting them sit on his tongue before swallowing them down. He groans himself at the taste, rich and heady, and if his body's reaction is telling, an aphrodisiac. Bruce goes from excited to desperate, barely keeping from starting to rut against the covers underneath him.
He moves back to the tip, wanting to explore it with his hands, his eyes, his mouth, and sees it’s changed. Before, there was almost a point to it, each of the ridges tapering off and meeting at the end, some eight nubs pressed together so the thinnest part was perhaps the size of a silver dollar. Now though, the ends of each ridge had split a little, looking more like the Buddha’s hand fruit than the cocoa pod, the change had him curious all over again and excited to see what became of it. He sits back with some effort and has Clark move with him to be sitting against the pile of pillows at the headboard so they can both see it change together. As much as he wants to get his mouth back on it, and even more wants to get his own dick involved, he sticks to hands to preserve visibility and control.
He licks his palm, then every finger, looking Clark dead in the eye with clear intent, then drops his hand back down to spread his saliva out, letting it coat Clark. The effect is immediate, the ridges continue to spread out, becoming what can only be described as tentacles, which once they are separated down to the base begin to move independently. They curl around his fingers, pulling them in towards their center which itself has a new orifice. It is wet with the same fluid Clark emitted earlier, and just open enough to look terribly inviting, so when the tentacles usher his fingertips to it, he obliges.
He touches just the first segment of his right pointer finger to it, testing the give and looking to Clark for his reaction, enjoying the way that pushing in up to that first knuckle makes Clark’s eyes go hazy and his jaw - which had been loose since the tentacles began to spread - drop open with a gasp. He rocks it in and out, teasing the feeling until the tentacles become more insistent, pulling and tugging, trying to get more of him inside. He allows it, letting his finger be dragged in up to the knuckle slowly, groaning at the tight wet heat he finds, the way the muscles inside seem to be sucking at him, trying to pull more and more inside. He pulls back, tests the tips of two fingers and finds Clark yields to them easily, but is no more or less tight around two digits than one. He rocks them inside, brushing the skin inside looking for any erogenous zones like a prostate or clitoris, but not finding anything obvious. Still, the motion has Clark grabbing at his wrist just a little harder than he normally does, his control clearly strained.
“Need- Bruce, Bruce I need,” but Clark doesn’t seem to know what he needs, or how to finish the sentence. Only that he needs and knows Bruce can and will provide.
Bruce can only assume that what Clark needs is more, perhaps more inserted into him, more bodily fluids to continue the process, either way, the next step is fairly clear. He extracts his hand from the tentacles though they try to keep him there, then moves so his knees are under Clark’s thighs, bringing their pelvises together. The appendages find Bruce’s dick immediately, gripping him and pulling in and in and in, the sensation is unlike anything Bruce has felt and Clark seems just as stunned. One of the tentacles comes up and swipes at the pre-cum beading at his tip, shuddering with it and then moving to rub against others to spread the fluid among them. They grip him tighter, tugging him forwards until Bruce has to shift his hips to get the angle right, hand reaching out to hold Clark’s as his dick is ushered inside. Clark tenses and then goes instantly boneless, his eyes are open and he’s still holding Bruce’s hand firmly, but the pleasure of being filled is clearly overwhelming. The muscles he’d felt with his fingers pull just the same on his cock, the feeling overpowering everything else and making him want to be pulled in and kept there forever.
Clark’s mouth moves to take his, and they stay like that, connected and still and rapturous with pleasure. Eventually Bruce’s drive to thrust wins out over the urge to just stay as deeply buried as he can and he begins pulling back just enough to grind back in, pulling further noises from Clark. The tentacles are dragging at him, compelling him to return, brushing anywhere they can reach and wrapping around the base of his dick on the outstroke to keep him as connected as they can. He reaches his free hand down to tangle with them, holding them and letting them grip his fingers back. In doing so he finally finds what he was searching for, at the very base of the tentacle closest to Clark’s stomach is an area with a distinct texture, invisible to the naked eye, but discernible with his fingertip. As he brushes it, Clark’s groans get more desperate, his hips arching up into the touch and hands starting to scrabble on Bruce’s shoulders, uncoordinated in a way he never is.
In the insertable pod form this erogenous spot would be perfectly stimulated by another's tentacles and the rim of their hole, and opened up it could easily be stimulated like this with hands, or with other tentacles. He tries different strokes, circling it and rubbing back and forth, tapping on it, with varied pressure and speeds, and settles on the one that makes Clark clench even tighter around him. Clark has fallen completely to pieces beneath him from the pleasure they’ve found and it makes Bruce glow inside to know he’s managed to wreck Superman like this. That he gets to have this.
Around his length, Clark gets wetter, tighter still, grunts out his name like it hurts, and absolutely shreds the sheets in his grip. With a display like that, Bruce is helpless but to follow, burying himself deep one last time and giving Clark everything he has left in him. They lay like that panting until Bruce softens inside him and has to withdraw from the sensations, they watch as Clark’s biology reverses. First the tentacles straighten into the bud, then the bud retracts into his body, leaving him with the tidy slit he’d had at the start, now full of both their release, though it is impossible to tell from the outside.
They are quiet together for a moment before Bruce remembers he promised to share his thought processes on Clark’s anatomy and resumes the dialogue.
“The form of the reproductive organ seems dependent on fluid sharing; the current hypothesis is that if only enough is applied to bring the pod format out, but not enough to open it, it could be used as a phallus.” He moves to wrap Clark in his arms, his least wet hand going to pet ruined curls, “presumably fluids donated while aroused could be stored and used later by a singular Kryptonian, unless there are more factors we don’t understand yet. We’ll need to do some tests, get a baseline, figure out controls…”
Clark lets him continue on without interrupting, enjoying feeling loose and sated in a way he’s never been before. The sound of Bruce applying that powerful mind to the task lulls him into a well deserved nap.