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Superman’s mouth was uncannily perfect.
It was symmetrical, colourful, plump. In his research, Bruce had come across photos of him as a child, mouth askew with crooked teeth. None of that disjointed anatomy remained. The faded red hue was perfectly distributed, the skin unflawed as if it had never been chapped in its life. His cupid’s bow sat right down the center line of his face, each corner lifted the exact same amount. It was utterly infuriating.
Bruce had sat through untold surgeries to get his face into playboy order after punches kept breaking his nose and his jaw. His lips were perpetually cracked. A tattoo returned the colour and shape to his cupid's bow after scarring had taken that away. For all his cowl’s protection of the upper half of his face, his mouth would never be the same. He’d lost the lips that had once kissed his mother’s cheek.
Superman flipped through the papers in his hands, then passed them to Diana on his right. She passed them to Ollie, as Clark cleared his throat. Then cleared it again. He bit his bottom lip, a nervous tick of his; it left no indent.
“I’ve been invited to visit Zwofve,” he announced. He barrelled forth despite the giggle across the table. “As you may know, the international trade hub there is one of the largest in the sector. They specialize in interspecies relations. Having heard of my presence here on Earth, they have offered to host myself and an Earthling to add ourselves to the current roster of connected species.”
He nodded in Hal’s direction. “I spoke to Green Lantern about this, and, while I don’t wish to leave Earth for too long, he encouraged building this connection.”
“The Lanterns don’t have a strong foothold there,” Hal filled in. “They’re trying to act as an independent inter-planetary organization and rarely collaborate. Any ins we can have…”
“Exactly.”
That shy twist crossed over his lips again, before they straightened in resolve.
“They asked that I bring a mate.”
His voice carried throughout the meeting Hall. Silence. Then laughter.
“They said—It’s to see how Kryptonians adapted to life on Earth.” He stumbled as he tried to speak over the cajoles. “Will you— Look, it’s not my—”
“Quiet.”
Bruce’s growl silenced the flock. A petering giggle hiccupped. They looked to him, soundless, though the teasing smiles remained.
“Continue, Superman,” he ordered. Those damned lips smiled gratefully in his direction, and Bruce turned around to yank a paper copy from Katar’s hands so he wouldn’t have to look at it anymore.
It was another moment before Clark spoke. “I wouldn’t need to be biologically compatible with the”—cough—“mate. The point is to demonstrate a relationship despite that barrier. I’m… hesitant to ask a civilian to come along, though I know some that can act as backup options if it does not work for any of us.”
Ollie’s distinctive wolf whistle interrupted him.
He ignored it. “I’ve detailed the mission parameters myself and Hal put together in the document that you all should have received by now. It would take a couple weeks, ideally leaving by the solstice. While I’m not sure what exactly would be expected of us on the surface, the document outlines our best guess. I know it’s a high ask. Please give it a look and get back to me next week if you’d be willing to accompany me.”
Bruce flipped through the pages as he talked. It was formatted as a routine mission outline. Diana would probably accompany Clark, maybe Barry if he could get time off work. If desperate, they’d try to sneak in Hal. An illogical twinge twisted in his gut. He couldn’t go, even if Clark wanted him to. He had Gotham to take care of.
“Kal,” Diana leaned forwards. “Wouldn’t this be more dependent on who you are most comfortable with? I expect a number of us could make arrangements to accompany you if asked, myself included. But have you already…?”
“My, uh, preferred partner isn’t available.” He rubbed the back of his neck, as if it were inevitable and not distinctly odd that anyone would turn Superman down. “So if you all could get back to me next week, that would be great.”
Arthur leaned back in his seat.
“Why wait?”
He looked pointedly in their direction. Bruce felt a sudden chill of dread.
“Batman has been staring at your lips all meeting. Just take him.”
No. No, that is not what—
All eyes turned to him. Clark distinctly looked away.
Bruce bristled. “I have not been staring at Superman’s lips.” The doubtful looks did not seem convinced. “I was trying to match his dental arrangement to a series of bodies found near the Gotham sewers. The killer clearly had non-human strength and jaw shape—”
That did nothing but offend Clark. “I have not been eating civilians in Gotham! Why are you even considering that it would be me when you have a man named Killer Croc roaming your—”
“Killer Croc has been working with Task Force X in Macau for the past two months. He is out of the picture. A rogue Kryptonian—yourself or otherwise—is not.”
A flash of red burst across Clark’s eyes, then he turned with a glare to the rest of the table. He stifled it before speaking.
“We’re moving on. Shayera, you had another update on interplanetary affairs?”
“Batman.” Clark’s warm hand landed on Bruce’s shoulder as he tried to make a quick exit. The meeting had been called to a close seconds before, and the rest of the Leaguers filtered around them on their way out. He ignored their pointed looks.
Clark took Bruce’s silence as a greeting. “I wanted to apologize for earlier. If the bite marks found do resemble Kryptonian’s form, I’d be happy to help in any way that I can.”
Bruce searched back through his lie. While the bite mark investigation was sitting in the priority folder of his batfiles, the theory of Kryptonian involvement was… a necessary fabrication to diffuse a dangerous path of conversation. Waylon Jones had been released from Task Force X three weeks ago and returned to Gotham soon after.
But… the culprit still hadn’t been confirmed.
And Clark was leaving soon. With someone else.
“Med room.” Bruce ordered.
“Now?”
He started walking down the hallway towards the infirmary. The sway of his cape was a familiar weight at his back. “Unless you have prior plans?”
“Uh, nope.” Superman floated after him. “I’m free as a bird until someone calls.”
He couldn’t hear Earth from the Moon’s Watchtower. Bruce tried not to let the potential for uninterrupted time go to his head.
Clark was uncharacteristically quiet as they made their way down the hall. His typical small talk faltered off after Bruce’ typical grunted reply to, “How’s Gotham? Aside from the, killings, you know.” Besides their capes, and the small creaks of Bruce’s joints, they were silent. Superman had no footsteps; Bruce’s made no sound.
He pushed open the infirmary door and let Clark float through the room while he gathered his supplies.
“So, uh. How do you want me?”
Bruce took a moment to wrap his thoughts into proper order. “There should be a stool next to one of the cots. Bring that to the central station.”
“For you or for me?”
“You.”
He pulled his prepared cart over. Superman blurred and then sat gingerly on the apparated stool, spreading his legs so Bruce could step up close. The height difference set Bruce a foot higher than him. Once again, Bruce tried not to let it go to his head (or his forced-steady heart).
He considered the sterile gloves for a moment—best to avoid contamination of the saliva samples—and removed his gauntlets. He pulled on the latex with strict precision. And if his fingers faltered a little with the heat of Clark so close to him, watching him? He shook the distraction from his head. He had a job to pretend to do.
“I mostly need a dental cast from you,” he said. Clark looked up at him as he approached with a pipette and a test tube. “But a saliva sample wouldn’t hurt.”
Clark nodded. His mouth remained shut, and serious.
“Do I have to force this past your lips or will you open for me, Superman?”
He dropped his jaw at that. Bruce touched his cheek, guiding him wider with the faintest pressure. Clark angled as asked, eyes on his.
“Have you ever been to the dentist?” Bruce asked as he drew a sample from near Clark’s back gums. He was—wet. Salivating far more than a human would, from no apparent source. Bruce noted that down with complete impartiality in the file in his mind.
“Ah, no,” Clark said as Bruce drew back his fingers and pipette. He packaged up the sample while listening. “Really any doctor’s trip was discouraged, even before I got my powers. It wasn’t entirely confirmed that I was an alien from the start, but Ma and Pa had enough suspicion that…”
“Not worth the risk.”
“No.” He smiled sheepishly when Bruce returned and opened up instinctively. Bruce ran his fingers over those familiarly odd teeth and gums.
Half of them were similar in shape to those of a human’s, but ordered wrong. On the top jaw, central incisors led to two sets of canine-esque teeth, then something similar to a bicuspid, then canines again. They were followed by two wide inverted molars(?)—square, and pointed into a dull peak like the Manor’s roofs.
The bottom jaw had two central incisors as well, but where the top jaw had canines, it had bicuspid, and vice-versa. He had four of those pointed molars, only thin this time and arranged in a square.
It was fascinating.
Clark swallowed.
“Don't do that,” he snapped. It brought far too much attention to his lack of a uvula—lack of a gag reflex—while Bruce was trying to memorize the curvature of the T4 canine.
“Sowrry,” Clark mumbled. His tongue slid against Bruce’s fingers as he spoke.
Bruce hastily pulled them out.
Spit shone on the gloves. It didn’t look much different than that of a human—perhaps a little glossier, tinted faintly pink. He hadn't run any tests on the saliva yet, but he doubted Clark could transmit any diseases. If he could, it wouldn't be a poor way to die.
Clark watched as he lifted his index to his mouth and licked.
Bruce frowned. “What have you eaten today?”
As a man who’d never been to the dentist before, Clark took Bruce’s departure from standard procedure in stride. “Uh, just a salad and eggs.”
He hummed. Probably can't get away with tasting it again. The gloves peeled off awkwardly before he tossed them in the biohazard bin.
Clark leaned forwards as Bruce stepped back to prepare the cast. “Was it… bad?”
“It was spicy.”
“Oh.”
“And unless you’ve eaten recently—”
“I haven't.”
“—then we can assume it's either a default state or brought on by something else recently. Have your partners ever commented on this?”
The casting putty was hard under his palms. He started rubbing it, warming it to malleability. Clark was silent.
Bruce looked back at him. “No? So it passed as normal to them. And I assume it's regular enough that you haven't noticed this as special yourself. Can you think of anything else that might cause this?” It could potentially be an allergic reaction that Bruce specifically was having—some cosmic sign that this was not allowed.
It was another moment before Clark spoke.
“You know. I uh. I haven’t really kissed people enough. For them to comment on it, that is. Mostly uh. Chaste kisses. Closed mouth. And stuff. I wasn’t really that popular as a kid, and by the time my face straightened out I was worried about my teeth and whether they’d notice and I mean I still wasn’t that popular and I’ve been pretty busy since then and—”
“Clark. Superman. It’s alright.” Bruce stared down his panic. “It just means we have a limited set of data.”
He swallowed. “Right.”
“And stop wringing your hands, you’re going to tear another hole in your suit.”
The finger strap he’d been fiddling with snapped back into place, looking only a little worse for wear.
“I’m going to take a print of your teeth now. Can you swallow back your saliva for me?”
Clark did as he asked, his eyes locked on Bruce’s as the man approached with a makeshift puck of putty. When a finger touched his lips—those flushed, barely kissed lips—he opened for him again. It was hard to think of anything except the information he’d just received. It changed the parameters in his head. They’d have to run some more tests.
Bruce slid the putty disk into his mouth. He touched Clark’s jaw.
“Close your mouth gently. Be careful not to break through the mold.”
Slowly, Clark sunk his teeth down. As Bruce waited for the imprint to set, he couldn’t bring himself to lift his fingers from that too-perfect cheek.
For a moment, his mind flashed to the upcoming mission and the thought of Clark having to play intimate with Arthur or Guy or someone else he didn’t trust. Someone who didn’t know the taste of his saliva. Would they react in shock? Would they sit through Clark’s stammered disclaimer? Would they levy judgement against him, or, selfishly worse, would they like it?
He swallowed. Clark’s clear blue eyes, pupils blown a little wide, watched his throat work. Then they met his.
“While you’re here, we should test the detectability of your Kryptonian teeth from the outside of your mouth.”
Clark nodded, slowly.
Bruce traced his fingers over his cheek, prodding gently. The skin didn’t give way as much as it could have on a human. It was warm to the touch. He could faintly make the distinction between each individual tooth. Too much was covered by the putty. He’d have to repeat it later.
He held up his hand, three minutes left for the cast to set.
“I had braces as a kid. Bright blue ties. I hated it. I had two years of braces-free life after, before I said the wrong thing and had my front tooth knocked out. If you look now, you’ll see a number of implants and rods.” It was always unnerving knowing Superman was looking through him. One wrong flex of his eyes and Bruce would go up in flames. “I’ve lost plenty more since, of course. My face is a medical miracle of reconstruction.”
Unwanted pity pooled in those eyes that watched him with rapt attention.
Bruce turned away, rearranging the supplies.
“My orthodontist would give out little toys from a treasure chest when I was growing up. I grew quite a collection of tiny dinosaur figurines.”
When he looked back, Clark was still looking at him. Rude.
They waited the remaining two minutes in silence.
“This may take a moment to unstick depending on the composition of your teeth,” Bruce warned.
Clark flexed his jaw after he removed the casting, then bared his teeth. Bruce bent down to check that no putty remained.
“All clear.”
Clark hummed. “Anything else, doc?”
“I want to run the external identification test again. Couldn’t get a clear result with the putty in your mouth.”
“Alright,” he agreed easily. Clark leaned his face into Bruce’s fingers before he’d even fully reached out. His cheeks were inhumanly soft—no clogged pores or scares or acne interrupting the smooth slide of Bruce’s fingers. Soft baby fuzz covered his jaw. Bruce allowed himself a second to stroke over his cheek with his thumbs, cupping his face. As he pet him, Clark’s eyes fluttered shut.
This wasn’t smart.
Bruce increased his pressure and slowed his swipes, pressing his thumb into the hollow of his cheeks. The teeth were easier to identify now. The odd assortment of canines were passably disguised. They had similar width and length to those of a human’s. If one did not look inside, they may not notice their uncommon shape.
He shifted his hands.
His thumb passed over Clark’s lips.
Like he’d observed, there were no flaws in them. The skin was stretched into an uncannily intact plane. The typical small wrinkles that covered a human’s lips were replaced with a smooth, plump, shine. It was soft and giving to the touch.
Unobserved, he allowed himself to slip in control, just a little.
He pressed the tip of his thumb to the gap between Clark’s lips.
Those impenetrable lips opened just enough for his nail to hit the front of those teeth. It was nothing compared to the fingers he had in there before, but the air felt different. Charged.
Clark opened his eyes, and looked up.
Bruce had made a career—two, in fact—reading people. As Batman, he read the flex of their muscles and the shape of their strikes, learned the form of their martial arts and could predict where they’d next hit. As Bruce Wayne, he read the widening of people's eyes and the way they turned into him, caught the intention behind their deals and the way they shook his hand. He caught their attraction to him.
Kryptonians may not be so different in that regard after all.
Superman could not blush, but he leaned into him, opened for him. Bruce felt the uptick of his pulse under his thumb. Those brilliant blue eyes that held his gaze had wide, hungry pupils. His breath caught.
He shouldn’t. They shouldn’t.
But, to Alfred’s great chagrin, no one ever said he made smart decisions when confronted with a beautiful face.
“Humour me,” Bruce murmured as he leant down. For science, he justified, as he slid out his thumb and angled Clark’s chin up.
For you, he knew, as he kissed him.
It was a simple press of lips. From what feeling he had left in his, Bruce tested the soft give of Clark’s. That flawless skin felt just as smooth as it had to his hand.
When Clark didn’t pull away, Bruce dipped out his tongue and softly traced it along the seam of his lips. Just a hint of that saliva burn could be found. The rest tasted… sweet, almost. Addictive. His heart threatened to speed up. He wanted to stay here for hours, feeling the half inch of Clark against him.
He breathed in—smelt nothing—then lifted off.
Clark looked at him in an expression Bruce knew to be of forced-neutrality. He stared at Bruce’s lips, then up beneath the whites of the cowl’s eyes. Then, curse him, he must have found what Bruce didn’t want him to see, for a beautiful smile crept across his face.
Bruce scowled. Clark smiled wider and grabbed him by the clasp of his cape, pulling him back in.
It was harder to kiss him this time, when it was starting to feel like something more than just science—something that wrenched a little too close at his heart, that held him a little too tight and ran its hands over the back of the cowl as if searching for hair to hold.
Bruce kissed him firmer this time, opened his mouth. He tried to remember that this was one of Clark’s first times but any caution was hard when Clark was so eager, and when he’d wanted him for so long.
“Open your mouth,” he muttered, and, like all those times before, Clark obliged. He swept his tongue inside—just the tip at first, just testing. The spice was stronger here. It tingled across his tongue and onto his lips. Clark’s teeth were covered with it. And when their tongues met—
He pulled back in shock.
“Are you all right?” Clark chased after him, panicked.
“Hngh,” Bruce said, instead of, That’s concentrated heat. He wiped his tongue on the back of his sleeve trying to tame the fire. It barely helped.
“I—Oh, great scott, Bruce, I’m so sorry.” His hands blurred through the air aimlessly.
“Hnaghh,” Bruce reassured, meaning, It’s alright. I liked it. He grabbed Clark’s arm when it passed by at a safe enough speed to not wrench his own out of the socket.
Clark was too mortified to notice, blubbering something charming like, “I shouldn’t have—I’m so—Is there anything I can do to—”
Bruce was considering kissing him again, tongue be damned, when Clark trailed off. His hands came up and clasped Bruce’s face.
“Stick out your tongue,” he commanded.
Bruce raised his eyebrow.
“Now’s not the time to be pretty, Bruce. Stick out your tongue.”
It was getting far too hot inside his mouth anyway. Bruce stuck out his tongue. Clark leaned in until only two inches remained between them, and, with his hands on both sides of Bruce’s face, he blew.
Cold air rushed over his mouth.
The burning was overtaken by a chilled sense of relief. When Clark pulled back, the pain had subsided into a faint tingling sensation.
Bruce grunted a question. His numb though blissfully painless tongue hung out of his mouth.
“I think it’s some sort of… defense mechanism? Consent matrix?” Clark reached up and rubbed his tongue gently. “I guess you’re supposed to pair the two solutions together to neutralize the kiss, otherwise it, uh. Hurts. I’m sorry,” he said. “I should have known that.”
Bruce shook his head. “You hah oh easohn ooh.”
“Yes, I did. It’s my body. And it hurt you. Can you imagine the danger if it had been a civilian? If I couldn't have revealed the freeze breath too? Can you imagine if I had to reveal the freeze breath?”
His arms were tense as Bruce grabbed them. He slid his tongue back in his mouth as it regained sensation. Clark averted his eyes, but didn’t pull away as Bruce kissed him again. Closed mouth and chaste. Simple.
He leaned their temples together and kissed his cheek too, for good measure.
When he pulled back, Clark met his eyes again.
“You jush have ooh kish eoble ooh ohw ourr i’en’i’ee,” he stated. It was far too revealing of a confession. He turned away.
“What was that?”
Bruce busied himself with the supplies cart.
Clark touched his arm. “What was that, Bruce? I just have to what?”
He flexed his tongue, then took a deep breath. He tried again. “You jush have to kish people who know your idendidy.”
He waited for Clark to put the pieces together.
Clark chuckled, “Yeah, I realize that now.”
Silence. Bruce put a cap on the test tube.
“Hey, Batman?”
He placed the cast in a circular container.
“Are you, in your roundabout fashion, saying you’d like to go to Zwofve with me?”
He tidied a stack of old notes on the side of the cart as arms tentatively wrapped around him from behind.
“You see, I hadn’t asked you first because I knew you wouldn’t want to leave Gotham.” His voice was warm and smooth right by Bruce’s cowled ear. “But you were my preferred partner.” An audible peck was placed somewhere on Bruce’s neck. “And, all things considered, you don’t seem to be against kissing me.”
Bruce briefly touched the back of Clark’s hand in acknowledgement.
“I still don’t particularly expect you to agree. But Kara can look after Gotham if you’d like and—”
He spun around in those arms. They loosened to let him as he pointed a finger against Clark’s chest. “Supergirl is not looking after Gotham. I have other support I will call on.”
Clark smiled, beautiful and wide, with four more canines than normal. “So you’ll come?”
“I haven’t agreed.”
“It sounds like you want to.”
“I’ll need a week to plan.”
“A week is fine.”
“We’ll fight a lot on the trip.”
“I don’t expect anything else.”
“And there’s a lot we’ll be expected to do that I don’t think you’d done before.”
“I trust you to guide me.”
“And—”
“Batman?”
“Yes.”
“Will you come with me to Zwofve?”
“If you want me to… I… Yes. Barring any emergen—”
Clark kissed him. It was simple, and closed-mouthed, and sweet. And when it opened, it burned a little.
But that was alright. They’d have time to perfect it.