It had been awhile, since that night.
The night that Lilith made a lot of mistakes.
Jack had come up to her in the throes of puberty, and asked for her help with his... arousal.
The brat was very insistent on someone taking care of it, and she didn't want him to go to Mom, and she might've snuck some of Dad's beer...
...so that's how she had sex with her little brother.
She knew, morally, it was fucked up. She'd always been a rebel, a delinquent, she liked breaking rules, but... He was 12. She was 17. Technically a minor too, she didn't know what the legality on that coupling would be, but frankly, she didn't want to know.
She told herself that one night would be it. But god, something about it... The size difference, the way he so completely trusted himself to her, his cute little moans, the thrill of her own little brother's cum flooding her unprotected womb...
The way he so earnestly confessed his love for her after the fact...
...She couldn't deny that their encounter sparked similar feelings in her.
So, they started... dating? She guessed...
Making him keep it a secret was tough, he was still a blabbermouth kid at heart, and she wouldn't change that about him, but god it was dangerous sometimes.
They never did anything sexual again, though. Closest they got was a french kiss that they had to interrupt because their parents got home.
...until, one night, Jack suggested they go on a date. A big fancy romantic date in a restaurant.
The idea made her heart race, and she figured it would be possible to pass it off as a big sister really treating her little brother, so... she agreed.
She helped him get all dressed up in a little suit, because god knows the brat couldn't put it on himself, and she put on a nice dress, a sharp contrast from her typical tomboyish jeans and jackets, and maybe a tad too revealing for her cover story, but she didn't think that far ahead, and they headed out.
Everything was going great. People looked at her a little weird, but just for her outfit. In retrospect, it actually took their attention away from the suspicious possibilities with her and her brother, so it was a good choice.
The waitress even praised her for spoiling her little brother. Boy, if she knew how much she really spoiled him...
Things were going fantastically. It was fun, and in the quieter moments where no one else could hear them, surprisingly romantic... as romantic as a 12 year old could be, anyways. Sweet more than anything, she supposed.
...Then, he pressed up against her side from his spot from the back of the booth.
And his high pitched voice came.
"Big sis... I'm so horny..."
"W-what? H-here?"
"Yes... Please, take care of me?"
"B-bro, there's so many people here..." She whisper scolded, looking around the place to confirm her fears. "That would be so bad..."
"Pleeeeease? I really need you... I need inside you... I love you..." He insisted, and began grinding against her bare thigh through his pants...
...she should've worn a longer dress.
And never had a kink for the thrill of possibly getting caught in public.
"S-shit... Y-you're such a brat..." She gasped out, shaking a little.
She looked around. They WERE in a fairly isolated corner of the restaurant...
...
"O-okay fine... But you HAVE to be quiet. Got it?" She firmly said.
He nodded enthusiastically, and didn't say a word further.
She sighed deeply, contemplated her life choices, and shifted her position to be sitting slightly on top of him, half of her still sitting on the seat.
If someone walked by, she didn't want them to see her on top of her brother right away. She wanted them to see her sitting on the seat first and foremost. Maybe they'd brush it off as just closeness and not... Well, closeness.
She wrangled into his pants, and managed to pull out his dick, already hard.
"Y-you weren't kidding... You are horny..." She muttered quietly, as she began stroking him.
He moaned, and she had to quickly slap a hand over his mouth. "Quiet! I said quiet, brat..."
He nodded. "S-sorry, sis..."
She couldn't stay mad at him. Not with that cute voice.
She knew she needed to get this over with quickly, so she maneuvered herself over his dick, hidden by her dress, and slipped her panties aside.
"Qui. et." She insisted, before lowering onto him.
They both moaned at about the same intensity as they finally rejoined after god knows how long apart...
She slapped a hand over her mouth, roughly obscuring her moans as she began to ride him.
He followed her lead, covering his mouth, but he wasn't as good at it, his cute little squeaks of pleasure still escaping.
It turned her on more.
She forced her eyes open amidst her pleasure to look around the place, to make sure nobody had seen them.
Nobody yet. Just the sounds of a LOT of people filling the air.
'Shit... Shit this is so bad...' She thought to herself, even as she felt her entire body tingling with how overwhelming arousing she found the situation, more than any she'd ever been in before in her life...
She tried to keep her riding subtle, but as she sped up, it became increasingly difficult to do that. By that point, speed was all she could hope for.
She bounced up and down on him over and over, every plunge of his cute little dick into her dripping wet pussy tearing another moan from her lips, into her hand.
She could already feel him throbbing inside her, climax approaching, and it was far too late to start thinking about the risk of him cumming inside her, so she just kept going.
She knew she had to make him cum inside her. He couldn't cum on the floor. There was no way she'd get away with dropping onto her knees and blowing him right there. She had to risk it again.
And that risk made her cum instantly.
"F-fuck, J-jack, b-bro!" She choked out intensely against her will as she tried her best to mute herself with her hand.
Of course, her noises and quivering and the intense clenching of her pussy walls against his inexperienced dick made him cum too.
"B-big sis!" He cried out, barely obscured, definitely could've been heard, as he poured his loud into his sister's pussy...
Lilith sat there, twitching and bucking as she felt his hot seed coating her insides, surge after surge of warmth flooding deep into her depths, soaking into her womb...
What if she got pregnant? Pregnant at 17, by her 12 year old little brother? That would be fucked. Not that any of this wasn't fucked.
And yet, again... Anytime she thought about the risk... It just made her cum harder.
She hated her kinks sometimes.
Finally, they came down from their orgasms, left collapsed there, panting desperately...
...The moment she got her mind back, she quickly pulled off of him, slid her panties back over her pussy before his cum could drip onto the seat, and helped him get his dick back in his pants...
Nobody noticed. At least, nobody said anything. She didn't know how they got away with it. They shouldn't have.
He hugged her. So innocently.
"T-thank you big sis... I love you..." His cute, tired little words came, and he kissed her cheek, and...
Her heart ached for him all over again.
'...Shit... Shit, I'm so fucked...'