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"Nai!"
Hands shoved deep in his pockets, Nai turned to face the sound of his name. It was his brother, of course - even if the sound of his voice wasn't unmistakable, there was the prosthetic hand waving in the air, the red of his jacket, the bright shock of golden hair peeking out from under his beanie. He didn't lift his hand in return. Instead, reaching for his brother's resonance, he pushed out, You're late.
"I know, I know," Vash panted as he reached him. In this sea of dull, dead-eyed humanity, he practically glowed. "Sorry, I would have called, but I forgot to charge my phone last night, and that would've been okay, but I didn't put it airplane mode, and you know there's no signal in the lockers there, so -"
Taking Vash's cheeks between his palms, Nai smushed his face together.
"Mmph," Vash said. He squinched his eyes closed as well, curling his fingers around Nai's wrists to tug at him. "Schtoppit."
"Use a coworker's phone next time," Nai sighed, but he let Vash pull his hands away.
"I forget your number," Vash admitted. Pressing his lips into a thin line, Nai squished his cheeks together again, wiggling his head back and forth until Vash was laughing and trying to duck out of his hands. "I'll - mmph, schtoooop! - I'll memorize it! I'll write it on my phone case!"
"Note inside your locker," Nai insisted.
"Okay, okay! Look, the train - "
On the train, Vash tucked himself up against Nai. This time of day, even three trains past their usual time, the compartment was crowded; Vash's feet slotted neatly against his, and Nai treated himself to an arm around his brother's waist to steady him while Vash peppered him with questions and ran through a breakdown of his day.
"We had a tour today," Vash said. "Big group of kids from the local elementary. The colony's doing well so far, I think. The headcount was twice what it was last year." Nai hummed an acknowledgement. There was nothing productive he could say to that - nothing that wouldn't start a fight. "They were so cute," Vash sighed. His head tipped against Nai's. "Just like the buds... I wanted to pick one up and squeeze them."
"We could have one of our own," Nai said, pitching his voice low. Gently, he squeezed Vash's waist, his fingers spreading out across his hip. It wasn't a particularly brotherly touch - and naturally, Vash shifted away, his eyes already scanning the faces of the other commuters. His brows pinched in.
"I dunno, Nai," he said. "Let's talk about it later. Hey, can we stop by the park? I heard the plant there went critical last week. I want to check on her."
Pushing when his brother set his mouth like that would only make him dig his heels in, especially in public. Nai grabbed the railing instead of Vash's waist and let himself hang.
"Of course," he simply said.
Despite the humans' mistreatment, their sister was fine. Silent except for her baseline hum, a soft, singular note rising in a wave over the thrum of her tank, she floated in her display with her petals wrapped tight. But she unfurled as they entered. Her long fingers reached out to press against her tank on the other side of the barrier. Always a risk, this, even when the park was deserted - Vash set a hand to the barrier anyway and looked up at her as she fully bloomed for them.
Brothers, she crooned, more an image than a word. He felt his channels prickle and tamped it down; beside him, Vash smiled.
"Hey, sis," he said for both of them, and Nai stood there while they exchanged a rapid-fire burst of images - passers-by and lab techs, the dim interior of some unnamed facility, a pigeon from the recently introduced flock. And then the children all in a row, faces upturned and bathed in the blue glow of their little sisters, eyes wide and mouths gaping in wonder. Their sister trilled to herself and fluttered in her tank. Then she lifted a slim hand and pointed, right at Vash's belly.
You? She asked.
Vash blanched. "No, no," he said, so quickly that it needled Nai. "Uh, no. Not us."
Disappointed, their sister sank a few inches and puffed out her cheeks.
"They're always like that!" Fuming, Vash flung his jacket over the back of the couch and slumped down after it. "Always! Even when you're not there! Stop smirking like that, dickhead."
"Like what?" As he passed, Nai grabbed Vash's jacket and hung it on the coat rack by the door along with his own.
"Don't play stupid," Vash groaned. "What's with you? Talking about knocking me up on the train…"
"So crude when it's just you and me. What do you want for dinner?"
"I'm serious!"
“So am I.” When Vash said nothing, only stared at him with a glower as surly as their sister’s, he said, “I would like to have a child. You like children - “
“Other people's children!”
“ - you love the chance to be around them, to hold them, teach them - “
“Nai, come on. We can't.”
“Why not?” Nai said. The thought had weighed heavy as a stone in the back of his mind for a while now - his brother, round with child, might be newly fearful for a life that wasn't his own. There'd been talk, according to Conrad. New regulations. More freedom, but at a great cost. Gently, as Vash dropped his head into his hands, Nai said, “Aren’t we allowed to have our own happiness? The humans control everything else about our lives - “
“We can't have a fucking incest baby!” Vash snapped, dropping his hands and fixing Nai with a sharp stare. “We're brothers, Nai. Twins.”
Nai scoffed. “Our own sisters nag us about when we'll give them children. Clearly it doesn't hold the same shame as it would for a human.”
“That isn't the point! Our neighbors aren't plants,” Vash said. “They're humans. They already -” With a shaky breath in, Vash braced himself before going on. “Did you know our next door neighbors have a kid? I didn't. Not until she showed up at the facility and told her teacher she wasn't supposed to talk to me because I'm ‘nasty.’ Because her mother knows we're together. I had to…” His fingers twiddled with a crease on the couch cover. “I had to get another tech to run the tour. And then I had to explain to my supervisor that I'm sleeping with my brother, and apparently, all our neighbors know.”
“Vash,” Nai started, but Vash cut him off with a raised hand.
“I just - I don't want any more friction. Okay?” He said. “We're lucky to have the peace we have. I don't want to risk it right now.”
Risk it. A dull, hot anger rose in Nai's chest, an achingly familiar coal lodged beside his heart. His brother played the fool, the harmless jester, but clearly he knew the truth. The humans suffered them to live. And Vash wasn't interested in fighting it. Slow change, he preached; time and patience, while their sisters withered under human care and their own lives were sharply curtailed. That they were able to live among the public instead of in a government facility as test subjects was a miracle.
They could thank Conrad for that; he'd anointed them with their unfortunate sister’s blood. Government jobs; a handful of humans given knowledge of their existence; a normal life, of a sorts, with a watchful eye hovering over their heads.
He was so tired, suddenly. It'd been a long day - his human coworkers were uncomfortable with him, and it wore on him, their flinching and shying away as he approached. Like he was a walking weapon, with the steel he could ooze from every pore. The last thing he wanted was to come home and fight with the only person on the planet who could understand him.
“Fine,” he said. The grateful slump of Vash's shoulders cut into him like a blade. Tamping down the hurt, he crossed his arms and asked, “What do you want for dinner?”
He spent longer than usual in the shower. The hot water unknotted his tense muscles; the steam cleared his head. By the time he cut off the stream and stepped out to drip on the bath mat, he was almost ready to let the day go entirely. For now, at least. Vash had said right now. It wasn't a no, but a not yet.
Not yet, not now… it could easily be never, with his brother's habit of dodging difficult conversations, but Nai could wait.
“Left any hot water for me?” Vash joked when Nai came into their bedroom, a towel wrapped low on his hips.
“No. Suffer.”
“You’re so mean,” Vash whined. He was already sprawled out on the bed in nothing but his undershirt and a pair of underwear, and as Nai pulled open a drawer, he propped himself up on his elbows and let his eyes roam over Nai's damp skin. “Hey, don't get dressed yet.” When Nai quirked a brow at him, Vash grinned. “Lemme look. You're all bundled up lately, all I see is those ugly sweaters you like.”
“It's cold,” Nai said, ugly sweatshirt dangling from one hand, “I'm dressing appropriately.”
“I can keep you warm tonight,” Vash said, waggling his dark brows ridiculously. Nai groaned, but when Vash motioned him over, he came all the same.
“I don't want to get sweaty again,” Nai sighed, even as he let Vash draw him down between his thighs. The towel slipped from his hips. This, he could never deny Vash; but that didn't mean he couldn't make him squirm. Dipping his head, he dodged Vash's mouth and planted a kiss on his cheek, chaste as good brothers should be.
“Nai, c'mon,” Vash groaned. His palm was warm on Nai's waist.
“Aren’t we brothers?” As he spoke, he let Vash pull him close, and he ground his hips against Vash's mound. Breath skipping in his throat at Vash's gasp, he said, “I thought I'd sleep on the couch tonight.”
“Asshole - yeah, we're brothers. And I want you to fuck me in a very brotherly fashion, so come on,” Vash grumbled, and when Nai laughed, he put his mouth to Nai's shoulder and bit him, hard enough to leave a purple imprint of his teeth.
“Ow!”
“Come here,” Vash said, cupping his hands around Nai's face. He pulled Nai in for a kiss. This time, he yielded, and for a moment, he lost himself to his brother. Vash's mouth was hot and plush, his lips soft against Nai's; his hands smoothed down Nai's neck and over his back. Somehow, they pushed Vash's shirt up and off, his underwear down, and then they were pressed together, bare skin to bare skin. When they came together like this, he could forget everything else - the humiliation, the control, the constant hum of fear under it all; it all faded away. There was only his brother, open and wet for him, his cock hot alongside Nai's, his pupils huge and dark with hunger when Nai pulled back to look at him. Everywhere they touched, Vash's skin sang with need.
“Condom?” Vash asked. His fingers curled around Nai's cock, stroking from root to dripping crown, where he swept his thumb through the bead of precum welling out of the tip.
“Ah,” Nai gasped. His hips twitched up into Vash's hand.
Once she'd come to understand the lingering touches between her boys, Rem had beaten it into their heads that with a sample size of two mature independents, there was no way to predict how, when, or if either of them could fall pregnant until it happened. Hormonal controls might not work with their biology; pulling out was off the table. That left only barriers.
“Yes,” he said, and Vash rolled underneath him to reach for their side table. He took the little foil packet without complaint. They'd had sex bare before. Only twice - once, Vash had reached into the package in the small hours of the morning to find it empty. Then, another time, Vash had said nothing when Nai pressed into him while watching a movie. His cheeks had flushed a deep, blotchy red; he’d been unusually wet.
Nai had pulled out before coming both times. But if he hadn't…
Obediently, he rolled the condom down his length while Vash shuffled his hips into place. With the tip pinched between his fingers, he hesitated.
It would be so easy to nick the condom. All it would take was a thought to summon a blade. The mechanics of sex would do the rest - the condom would fail, and Vash would notice. Or perhaps it wouldn’t, not fully. Perhaps Vash wouldn’t notice.
“Nai?” Vash asked. His fingers trailed along Nai’s thigh. “You okay?”
“Ah - yes,” Nai said. To excuse the delay, he stroked himself as if settling the condom. “It’s a bit…”
“Is it too tight?” Vash’s cool fingers joined his own, dipping down between Nai’s legs before palming him to spread his own slickness across his length. Nai shivered.
“It’s fine.” Brushing the thoughts away, he braced his weight on his palms as his brother guided his wrapped length to his slit. Vash would be furious; worse, he would be hurt. This peace they lived in, dubious as it was, would shatter. Without Vash, his life would shrink to meaningless drudgery.
But a little girl child, with blonde curls and a pale, round face similar to his own… Vash's silky heat wrapped around him, and Nai let the thought fall away again, focusing instead on Vash's sweet moan as he filled him.
“Mmh,” Vash hummed as Nai seated himself fully. The breathy tone of his voice, the way his lashes fluttered; Nai would never have his fill of this. “Nai…”
“I'm here, brother,” Nai murmured. When Vash kissed him again, he let himself settle against him fully, pinning him to the bed. Those long legs hooked over his own. It made pulling out difficult, but if that's the way Vash wanted it - rocking his hips back, unsheathing himself as much as he could without pulling away, he snapped them forward to fuck into Vash with a filthy slap. Vash's breath skipped out against his lips on a moan.
“Like that,” Vash gasped. His head fell back against the pillow as Nai began to rock into him. “Yeah - “
Nai kissed him silent.
Even through the condom, Vash was hot and tight, the slippery depths of him squeezing Nai's cock like they were shaped for him alone. Maybe they were; their sisters always acted as if they were a foregone conclusion, like their children would eventually toddle up to a tank to say hello. Heat pooled in Nai's belly with a tension that drew his stomach taut, and he thrust up against Vash hard enough to make his brother gasp.
“Fuck - yes!”
He did it again, and Vash arched underneath him. Sex with a condom was good - anything with Vash was good, any pleasant contact his brother offered him was welcome - but he thought of Vash's face gone cherry red, the wet suck of his sex around his bare cock, and he resented that thin sheathe separating him from his brother. His brother's skin hummed with dissatisfaction. The humans kept them apart in this tiny way, and his brother denied himself -
Sweat pooled in the small of his back. Vash was grinding up against him with every thrust, his plush lip caught between his teeth. He'd be beautiful pregnant. The image of Vash's belly swollen with their child rose in his mind unbidden. His brother, blue eyes soft and warm, radiant and round; a beauty mark on a tiny face, blonde ringlets, blue eyes with fine, translucent lashes. A small hand in his own.
Nai groaned as a shiver ripped through him. His cock throbbed in its sheathe.
“Hold on,” he gasped. Jerkily, he pulled back enough for his cock to slip free, the cold air snapping at his wet length, and he reached down to grasp the swollen head.
“What's wrong?” Vash's hands caught at his back, just shy of pulling him back in.
“Nothing, just…” The blade slipping from his fingertip was as natural as breathing. Carefully, he drew the blade along the top of the condom, right underneath the bubble of space left at the tip. It felt like nothing - only when he ran his finger along it again, the blade retracted, could he feel the finest slit in the rubber. He wrapped his fingers around his length and worked his cock like he was settling the condom again.
“Do you need a new condom?” Vash asked. His voice was sweet, breathy with want and spoiled pleasure; when Nai shifted back up against him, butting the head of his cock through his sopping folds, Vash didn't stop him. No, he spread his legs and lifted his hips to let Nai slip back into that intoxicating heat.
“No,” Nai breathed out. It didn't feel any different. Still wet, still tight - still less than it could be. “Just, ah… needed to adjust.”
Eyes closed to focus on the weight of Nai's cock inside of him, Vash only hummed in acknowledgement. His skin was electric everywhere they were in contact, and when Nai began to fuck him again, he slipped back into that hazy half-awareness as he chased orgasm on Nai's cock.
When the condom gave way after a few rolling thrusts, he felt it. The snap of it was subtle - the sudden heat, the slick pressure, Vash's wet walls gripping his bare cock, was not. His hips stuttered in shock. Vash seemed to feel it, too. “Uh - “ Eyes still closed, hands curled around Nai's shoulders, his brother huffed out a tiny sound. “Nai, um… mmh…”
“Yes?” Nai pressed his mouth to Vash's in a sloppy kiss. He didn't stop. Every thrust sent a wash of pleasure rolling up his spine; he felt it in Vash, too, the zipping heat jolting through him as their bodies finally came together as they were meant to, no barrier between them, their fluids mixing and pooling in Vash's cunt. The color was rising in his cheeks. His thighs clamped around Nai's hips.
“Feels k-kinda…” Nai drove his cock in deep, butting up against the top of Vash's sex, and his brother dug his nails in to hang on. Whatever vague suspicions had been forming in his mind slipped away, and he arched against Nai with a wanton moan. “Ah! Oh god, there!”
Of course he would never deny Vash anything. Especially not this. Curling his hands under Vash's hips, he pulled his brother flush and fucked him hard. As his hips slapped against Vash's ass, his brother went brilliantly pink, then red, the color spilling down his chest as sweat beaded across his skin like dew, exactly like it had the other times he'd been able to bury himself in his brother's hungry cunt without a condom blunting their compatibility. Wetness dripped out around his cock. Every thrust pressed more and more from Vash, until their thighs shone with it.
He should have done this sooner. Sex was meant to be like this between them. If Vash fell pregnant from this, Nai could fuck him raw as much as they wanted. The thought had him crushing Vash close. One child. Or two. Three, even. He could keep his brother full, full of cock, full of cum, full of children, safe and content in bed.
“Vash,” he groaned desperately. Vash's arms went around his neck; he scrabbled at Nai, his mouth open on a wet moan, and then his breath hitched and his back arched without warning. The sudden clutch of his cunt, almost painfully tight around his sensitive cock, made it clear even if the backlash of pleasure rushing through their connection didn't. His channels flared to life across his body, rushing out in a wave from his inner thighs, and he moaned as he came on Nai's cock. His own cum spilled between them.
“Oh my god, Nai,” he gasped in a rush. His sweaty cheek was pressed to Nai's. The pulsing waves of his orgasm went on and on - it was enough to pull Nai over the edge as well. With a guttural groan, he buried himself deep, slamming Vash down on his cock, and let himself spill inside of his brother. Pulse after pulse of cum poured into him. He pushed it all deeper with shallow, sloppy thrusts.
“Fuck,” Vash groaned against his cheek. Around Nai's cock, his sex was pulsing in hungry waves, as if the seed filling him had sparked some instinctive desire to draw it further in. “Mmh… don't pull out yet.” With a hand on Nai's ass, he held Nai still, his legs winding around Nai's while the aftershocks echoed between them. Finally, Vash slumped underneath him and turned his face into the pillow. His thighs relaxed, falling open around Nai's hips. “Oof. Wow.”
While Vash was limp and willfully blind, Nai eased back enough to slip his cock out and hooked his thumb under the elastic of the ruined condom. The entire thing had shredded - all that was left was a ring around the base of his cock. Rolling it down his shaft, he dropped it into the trash and pulled Vash close again, his half-hard cock brushing through Vash's folds.
“Mm, don't.” Vash's hand on his chest kept him from sliding back into that slippery heat. “Probably got cum all over your dick.”
“I know.” Nai slipped a hand between their bodies. Wet as Vash was, he likely couldn't tell his own arousal from Nai's seed - only the stickiness, the oozing whiteness, would give him away. Pushing two fingers into his brother, he swirled them around, then pressed them deep. His heart thundered in his chest, but he purred, “You're so wet for me today.”
“Yeah, I… that felt… mmh.” Abortively, Vash tried to close his thighs again. “S-stop, I'll come again.”
“So come,” Nai said. Pressing a kiss to Vash's neck, he pumped his fingers into Vash. Before long, Vash was moaning underneath him as another orgasm washed over him, and Nai pulled his fingers out and wiped them through the mess on Vash's stomach.
His own seed was mixed into Vash's wetness. It webbed between his fingers in thick, sticky streaks threaded through with white. He'd come inside of his brother. And his brother's body had exalted in it. Against Vash's thigh, his cock made its interest known with a throb and a twitch.
“Vash,” he said, “Can I…”
“Yeah,” Vash said. “Get a fresh condom, okay?”
Afterwards - after he'd thoroughly stirred Vash up, mixing his cum into the slickness still dripping from his brother's slit so that all that oozed from him was an indistinguishably creamy froth - he fetched a washcloth and wiped them both clean. He'd briefly contemplated piercing the second condom, too. He hadn't; it was enough to have inseminated his brother once. With any luck, that's all it would take.
He'd have plenty of time to fuck Vash after that.
Balling the dirtied cloth up, he tossed it into the laundry basket and stroked the back of Vash's sweaty thigh. “Shower?”
“Nahhh. In the morning.” Since Nai had come in him, Vash had been strangely boneless. He rolled over and reached his arms out for Nai to slide into.
Brushing the backs of his fingers over Vash's cheek, he pressed a kiss to Vash's lips. “You were enthusiastic tonight.”
“It, uh… it felt really good.” A blush rose on Vash's cheeks. “I started thinking about that time we had sex without a condom. Guess it got me worked up.”
“It did feel good, didn't it,” Nai murmured. His heart had lodged itself in his throat, but Vash only nodded. “If you ever wanted… I could pull out. You didn't get pregnant last time.”
Vash heaved a sigh. “That would work until it didn't, Nai. I dunno.” Another sigh; he wiggled in Nai's arms, tangling their legs together. “Maybe as a birthday treat.”
Nai hummed in agreement. Their birthday was only a month away - a month in which he could experiment. If he pricked the tip of the condom, would it tear? Would it leak enough of his seed to conquer any egg lurking in his brother's body? Would it fill his brother with this same loose-limbed pleasure that made him so agreeable, that made him come so hard he didn't notice his brother's spend oozing out of him? It would be a cover, at least. His birthday gift to Vash could be a child.
He would love a child, Nai knew, however much the pregnancy scared him. Pulling Vash close, he let his brother squirm around until he was spooned in Nai's arms, and he let his hand drift to Vash's flat, tight belly.
“Night, Nai,” Vash said. Reaching up, he toggled the light. Darkness rose up around them so that his awareness shrunk to Vash's warmth and weight in his arms. “Sweet dreams.”
Nai pressed his fingers against his brother's empty belly and imagined it full. Imagined his brother with a reason to prioritize himself - and their family. Nosing against the short crop of his hair, he kissed the back of Vash's neck and said, “Sleep well, brother. I love you.”