I slammed the door behind me and stared at my sister sprawled on her bed, legs spread, already fingering her wet pussy. She was twenty-two, same as me, and we'd been sneaking around for months. Tonight was different. She was ovulating and she wanted my load deep inside her.
"Get over here and fuck me," she said, voice low and nasty. "I want you to knock me up tonight."
I dropped my pants and my cock sprang out, thick and hard. I climbed on the bed, grabbed her hips and yanked her toward me. No foreplay this time. I lined up and shoved my dick straight into her cunt in one rough thrust. She gasped and her walls clamped down tight.
"Fuck yes," she moaned. "Breed me. Fill my pussy with cum."
I started pounding her hard, the bed creaking under us. Her tits bounced with every slam. I reached down and rubbed her clit while I fucked her, making her drip even more around my shaft. The wet sounds filled the room as I drove in balls-deep again and again.
She wrapped her legs around my waist, locking me in. "Don't pull out," she begged. "I want every drop. Make me pregnant."
I leaned over her, grabbed her wrists and pinned them above her head.
My hips snapped forward faster, the head of my cock hitting her cervix with each thrust. Sweat ran down my back. Her pussy felt hotter and tighter the closer she got.
"I'm gonna cum," she cried out. Her cunt spasmed around me, milking my dick as she came hard. Juices gushed out around my shaft.
I didn't slow down. I kept fucking her through it, chasing my own orgasm. The thought of pumping her full of sperm pushed me over the edge. My balls tightened and I buried myself to the hilt.
"Take it," I growled. Thick ropes of cum shot out, flooding her fertile womb. I kept thrusting shallowly, pushing every spurt deeper. She moaned louder, feeling me fill her up.
We stayed locked together, my cock twitching as the last drops emptied inside her. When I finally pulled out, cum leaked from her stretched hole and ran down her ass. She reached down and pushed two fingers inside, scooping some of my load back in.
"Keep it in there," she said with a dirty grin. "I'm not wasting a drop."
I rolled onto my back but she wasn't done. She climbed on top, grabbed my still-hard cock and sank down on it again. Cum and her juices squelched as she rode me. Her hips rolled and she ground her clit against my pubic bone.
"Round two," she said. "I want you to breed me twice tonight."
She bounced faster, her pussy sucking at my shaft. I grabbed her ass and spread her cheeks, watching my cock disappear into her. More of my cum squeezed out with every downstroke. The sight made me throb inside her.
I sat up, wrapped my arms around her and flipped us so she was on her back again. I hooked her knees over my elbows and folded her in half. The new angle let me go even deeper. I fucked her with long, hard strokes, my balls slapping her ass.
"Feel that?" I grunted. "That's me planting a baby in you."
She clawed at my shoulders. "Yes, fuck, yes. Knock me up. Make me your breeding slut."
Her second orgasm hit fast. Her cunt rippled and squeezed, trying to pull more cum out of me. I gave it to her. I slammed in one last time and unloaded again, another thick flood of sperm straight into her womb. She shook under me, eyes rolled back, taking every pulse.
We collapsed in a sweaty heap. I stayed inside her until I softened, then rolled off. She kept her legs up, hips tilted, letting gravity help my load stay deep.
"Think that did it?" she asked, voice hoarse.
I reached over and pushed two fingers into her sloppy cunt, feeling how full she was. "If not, we'll try again tomorrow. And the next day. Until you're pregnant."
She smiled and clenched around my fingers. "Good. I want my brother’s baby."
We lay there catching our breath, already planning the next round. Her pussy kept leaking my cum onto the sheets, but neither of us cared. This was just the start of turning our filthy secret into something permanent.
