Chapter Text
Kai and Nya had a secret. One they’d been keeping from the other Ninja since they’d reach the monastery… that being the true nature of their relationship.
Yes, they were siblings… but they were also something more. It had started when Nya was 13 and Kai was 15. Their parents had been gone for years already, and it would be another year and a half until the Wu would happen to stop at their shop.
Both of them were starting to feel things, to grow up. And naturally, spending most of their time around each other, those feelings were directed to each other. It’d started with just them being closer than before. Cuddling, holding hands, kisses to the cheek. But as time went on, they wanted — no, needed more.
It truly began when one day, frustrated, Nya pulled Kai down to kiss him as best she could. Her hands reached around his neck as their lips pressed together. Neither of them knew how to kiss properly, but they tried their best. Nya moved back finally, looking up at Kai with a sparkle in her eyes and her hair messed up. Kai looked at her with the same sparkle, his eyes practically glowing with love. His mouth ticked into a little smirk, and he winked before pulling her into another kiss.
Their relationship continued like this, kissing, making out, a bit of rubbing against each other, for the next year. The most they did was masturbate with each other.
Kai slid his hand up and down his cock, eyes locked onto Nya’s. His free hand was holding onto Nya’s, her hand clenching onto his. He wasn’t far from his orgasm, and just looking at Nya, fingering herself with two fingers and biting her lip, made it come ever closer. With a final grunt, he came, cum spurting out. Nya winked at him before she let out a moan of her own, cumming. She offered her fingers to Kai to lick, before moving down to clean up the cum from Kai’s cock.
Finally, though, on Nya’s 14th birthday, they truly had sex.
Kai found himself underneath Nya, her eyes glinting with that same sparkle she had all the way back when their relationship started.
“C’mon, Kai,” Nya said as she tore off her shirt, exposing her breasts. “I’m 14 now! We can have sex!”
“Nya, I’m just not sure,” Kai replied, trying to ignore the hard-on he had. At Nya’s pleading look, though, his resolve crumbled. “Fine. We can have sex.”
Nya pumped a fist in the air, moving down to kiss Kai before unbuckling his pants and taking them off. Then, positing herself right above, she slowly lowered herself down onto his cock. Both of them moaned in unison, as in sync as they ever were.
“F-fuck, Nya!” Kai groaned as Nya began moving up and down on his cock.
“I know, right?” Nya pinched her own nipple, pleasure clear on her face. “It feels so good.”
Seeing how much Nya clearly enjoyed it, Kai felt his last doubts fall away. He grabbed her hips, pulling her down harder onto his cock. She let out a yelp of surprise, but quickly recovered.
“Mmm, fuck me like that, brother!” Her words fueled Kai’s need, and he began fucking her in pace with her, increasing their speed. A wide grin stretched on her face as they fucked, her clit slamming into his pubic bone. Finally, after minutes, Kai couldn’t hold it in anymore.
“Nya, I-I’m gonna cum,” he whined, eyes screwing shut.
“Come inside me, brother!” She replied, only increasing her speed. Kai could do little but obey, his cum emptying itself inside Nya. Mere seconds later, she too came, a loud and breathy moan of his name on her lips. As their orgasms crashed over them, Nya lowered herself down to lay on Kai’s chest. She looked up and winked at him.
Now, they were at the monastery. They had to keep their relationship hidden from the others, but… they could still find time for each other.