I slammed the door behind me and shoved my sister against the wall the second we were alone in her apartment. "You really want this, Lisa? You want your big brother to knock you up tonight?"
She moaned and ground her ass back against my cock. "Fuck yes, Mike. I've been on the pill too long. Pull it out and breed me raw. I want your cum deep in my pussy until it takes."
I ripped her dress off, not bothering with the zipper.
Her big tits bounced free and I grabbed them hard, pinching her nipples until she yelped. "Strip the rest and get on the bed. Legs spread. Show me that cunt you want filled."
Lisa tore off her thong and climbed onto the mattress on all fours first, then flipped to her back, knees pulled wide. Her shaved pussy was already glistening. "Look how wet I am for you. Come fuck your sister and make me pregnant."
I dropped my pants and climbed on top. My thick cock slapped against her belly as I rubbed the head up and down her slit. "Beg for it. Tell me exactly what you want."
"Shove that dick in me and cum inside. Don't pull out. I want every drop. Breed me, Mike. Put a baby in your sister's belly."
I slammed in balls-deep on the first thrust. Lisa screamed and clawed my back. Her tight cunt gripped me like it was made for this. I fucked her hard and fast, the bed slamming the wall with every stroke. "You like your brother's cock stretching you open? You like knowing I'm about to flood your womb?"
"Yes! Harder! Fuck me like you own me. Fill me up!"
I grabbed her hips and pounded deeper, the wet sounds of her pussy loud and filthy. Sweat dripped off me onto her tits. Every time I bottomed out she gasped and begged for more cum. I reached down and rubbed her clit in rough circles until she came hard, squirting around my shaft.
"Don't stop," she panted. "Keep going until you breed me."
I flipped her onto her stomach, yanked her ass up, and drove back in. Her face pressed into the pillow as I railed her from behind. "This position's better for knocking you up. Deeper. You feel that? I'm right against your cervix."
She pushed back to meet every thrust. "Yes, fuck, yes. Cum in me. I want to feel it pumping. Make me pregnant with your kid."
My balls tightened. I buried myself to the hilt and let go, flooding her with thick ropes of cum. Pulse after pulse shot straight into her womb while she moaned and clenched around me. "Take it all, sis. Every fucking drop."
I stayed inside her, grinding slow to push it deeper. When I finally pulled out, cum leaked from her stretched hole. I scooped it up with two fingers and shoved it back in. "Keep that in there. We're not done."
Lisa rolled onto her back again, legs still spread. "Round two. Fuck me until it's overflowing."
I got hard again fast watching my load drip out of her. This time I took her missionary, holding her knees back to her shoulders so I could watch my cock disappear into her cum-slick pussy. "Look at that. Your brother's cum is already inside you. You gonna carry my baby?"
She nodded, eyes glassy with lust. "Yes. Breed me again. Fill me more."
I fucked her slow and deep at first, then faster, slapping my balls against her ass. She came twice more before I unloaded a second time, adding even more cum to the mess inside her. We kept going for hours, switching positions, her riding me, me taking her against the wall, on the floor, back on the bed. Every load went straight into her pussy with no condom, no pulling out.
By morning she was a wreck, cum leaking down her thighs, belly slightly swollen from how much I'd pumped into her. She smiled up at me, hand on her lower stomach. "I can feel it. I'm going to be pregnant. Your baby."
I kissed her hard and shoved two fingers back inside her. "Then we keep trying until the test says positive. Every night. Raw. Just like you wanted."
She spread her legs wider. "Start now."
