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They’d been on ship 3 for about two years now, having been rescued after the crash clinging to each other underneath a large scrap of debris as an attempt to shield themselves from the elements. Vash had been quick to warm up to the inhabitants of ‘Home’, as Luida had taken to calling the ship, but Nai had been much more cautious. Even now he was wary of any interaction he had, even with Brad and Luida who had become somewhat of surrogate parents to the twins. Since the accident Nai had been even more protective over Vash, never letting him out of his sight. Vash didn’t mind, though. Without Rem, they were each other’s only remaining family and Vash liked spending time with his brother. He didn’t get as grumpy about Vash’s lack of power anymore or hold his own over his head. They would help take care of the Plants on the ship together (Vash knew that was Nai’s favorite part), and at dinner Nai would let Vash have his serving too. Then, when Vash got tired they would curl up into bed together until Vash drifted off to sleep. He was never sure if Nai actually ever slept, but he knew his brother never moved from his side when he would rest, always waking up still pressed right to Nai’s side with at least one arm wrapped around him.
Then, one night when they were laying in bed together, Vash’s eyelids getting heavy, Nai sat up and began to dig his hands underneath their mattress, clearly searching for something.
“What’re you doing, Nai?” Vash asked as he rubbed sleep from his eye. Nai finally pulled a thin book from underneath the bed and sat back beside Vash.
“I found this in Brad’s room…” he said as he ran a hand over the cover. Vash could see now it was a magazine and he blushed as he took in the image across the cover. It was of a very busty woman dressed in only underwear with her breasts pressed around the erect member of a man. He started to say something but Nai was already flipping through the pages. Pages upon pages of pictures of human males putting their genitalia inside of human females. “This is how the humans reproduce, but I don’t think Brad is interested in breeding young… so I wondered why he would have this instruction book…” he looked up at Vash who was peering at the book through the slits between his fingers held over his face. “Then I saw him touching himself while looking at one.” Vash couldn’t help but notice the way Nai’s finger hovered over the penis in one of the images. “So it must be for more than just producing young.”
“L-like what…?” Vash asked, hands sliding off of his face as Nai blinked at him.
He shook his head. “I don’t know, but you and I have the right parts to try it. If you want to…” Vash’s face erupted in a new blush at Nai’s suggestion. “Please, Vash?” He looked at his brother through his white eyelashes, pleading softly. He never asked anything of Vash, always doing everything to make his brother happy over his own wants. He’d never once expressed his own desires before and Vash wanted to care for his brother just as much as Nai cared for him. He looked back down at the pictures on the page then back at Nai before nodding.
Nai pressed him back into their bed with hands on his hips leaning his face in closer to his twin’s, an exact mirror of his own features. “Nai…” Vash breathed softly, eyelashes fluttering as he can feel Nai’s hot breath against his lips. Their first kiss was soft, gentle, inexperienced, but it set off a flurry of butterflies in their stomachs and Nai quickly pressed his lips harder against Vash’s, devouring his mouth in the kiss as his fingernails dug into Vash’s sides. His younger brother whimpered softly, his own hands grabbing at Nai’s arms and clinging to him as their lips part and their tongues meet. Nai begins to slide Vash’s shorts down and Vash happily spreads his legs for him. He grabs Vash’s hips and roughly pulls them closer to himself before his hand slides between Vash’s thighs and gently brushes against his lips. Vash whines softly, pressing his hips forward against Nai’s hand as his long fingers slowly rubbed up and down his slit. He was getting wet already and Nai briefly pulled his hand away to examine the stickiness between his fingers. Vash whimpered, calling for his brother and arching his back so his hips jut upwards in a silent plea.
Nai lowered his hand back down and continued to touch him, thumb slowly circling Vash’s clit as he dipped a finger into his sex, feeling his walls contract around him. Vash watched him through near slitted eyes as Nai observed everything he did, every reaction to every touch. His sharp gaze analytical as he began to move his finger inside him, thrusting in short, quick movements. Vash cried out, cunt squeezing around him as his back arched. “Nai~!” Nai added another finger, gingerly working Vash open as he felt his cock harden beneath him.
He had touched himself before, in the showers, while he thought of his brother. Imagining scenarios like this in his head while he desperately tugged on his cock until completion, never imagining he would be able to actually get Vash into a position like this. He knew that Vash had never touched himself, though, and it gave him a rush knowing he got to do it first. He would never let anyone else do this, never let anyone else see his sweet gorgeous brother in this position. Vash pleaded to him, begging for more as Nai’s fingers thrust in and out of him. His walls clench sporadically and Nai can’t stop thinking about how they’ll feel around his cock, now dripping and aching between his legs. He pulls his fingers out, shushing Vash’s whine softly with a kiss before taking one of his legs and lifting it, spreading his pussy open farther. He sat there for a moment, enamored with Vash’s absolute beauty, until a whine brought him back to the moment.
“It is okay, little brother…” he assured, “I’ll take care of you.” He pressed the head of his cock to Vash’s entrance, feeling the way it twitched around his sensitive flesh, Vash’s hips trying to raise further. Nai captured Vash’s lips in a new kiss as he slowly began to press his cock into him. The drag of his thick cock against his walls was the most immense pleasure he’d ever experienced and Vash gasped and whined over every inch until Nai’s hips were pressed against his. They stayed like that for a while, Nai sitting fully inside him as Vash gently rolled his hips, getting used to the feeling of him.
“Nai…” he whispered into soft platinum hair, his brother having busied himself with sucking marks against Vash’s fair skin. Nai pulled away, his blue eyes darkened with lust. “Please, Nai… more…” That was all Nai needed to hear and he quickly began to move his hips, his pace immediately strong and steady. Each thrust pulled a new whine or moan from Vash and he threw his head back against the pillow as Nai fucked into him brutally. Nai leaned down, light hair ticking Vash’s cheeks as he whispered sweet nothings into his ear.
“This is what we were made for, Vash… you and I…. We were made for each other , the perfect other half…” he pressed a kiss to the point where his jaw met his skull and Vash whimpered softly.Vash locked his legs around Nai’s hips, pulling him closer still. In return, Nai kept his pace steady, and watched as Vash stared at him with hazy, love struck eyes. Nai could feel the pleasure building deep in his abdomen, felt the way his dick twitched more and more inside of Vash, and knew he was close to his climax. He slowed his thrusts and reached down to gently rub his thumb in circles against Vash’s clit. Vash gasped and thrust his hips against the stimulation. “I want you to finish first, Vash…” he said as he kept rubbing.
Vash squeezed his eyes shut, a hand over his face, babbling nonsense until his pussy tightened, contracting hard around Nai’s cock. His hips stuttered and his walls spasmed with the waves of his orgasm. His legs around Nai’s waist tightened and help Nai deep within him. “Please, Nai- please- I-I want yours inside me-“ Nai was weak, Vash’s soft voice pleasing and desperate. When his orgasm passed and the vice grip his legs had on him slackened, he began to thrust again, pace now quickened as he chased his own release. It only took a few before he felt one final, strong twitch of his dick and his balls squeezed, spilling his seed deep into Vash’s womb. Vash’s eyes went glassy as the warmth filled him, body going slack and relaxed. Nai held him by the hips, never moving from his position deep inside of Vash until he felt the final waves of his orgasm pass through him. He then pulled his dick out halfway, watching as his semen spilled out from behind it, then slowly fucked it back into Vash’s swollen pussy.
“N-Nai…” he looked up at his brother, watching him try and form words. “Do you think… this is how Plants reproduce, too?” Nai wasn’t sure, but as he slowly began to move his hips again, he couldn’t help but think…
I sure hope it is.