I scrolled through her secret Tumblr one night and my cock got rock hard in seconds. There it was, post after post, my sister describing exactly how she wanted me to bend her over and pound her pussy like she was nothing but a dirty fucktoy for her own brother. "I want him to catch me touching myself and just take it," one caption read under a photo of her spread legs in tiny shorts. Another said, "Brother cock only. No one else gets how wrong and hot this is."
I jerked off right there in my room, reading every filthy word. She was 22, I was 24, and we still lived under the same roof. Our parents were gone for the weekend. The house felt too quiet, too full of possibility.
When she came home from work I was waiting on the couch, phone in hand. She walked in wearing a tight tank top and yoga pants that hugged her ass like they were painted on. "Hey," she said, then froze when she saw my screen.
"That's my blog," she whispered.
"Yeah it is," I said, standing up.
My dick was already pushing against my jeans. "You want me to fuck you, sis? You want your brother to ruin that tight little cunt?"
Her face went red but her nipples poked hard through the tank top. "I… I didn't think you'd see it."
I grabbed her wrist and pulled her close. "Too late. Get on your knees."
She dropped without arguing. Her hands shook as she unzipped me. My cock sprang out, thick and already leaking. She wrapped her lips around the head and sucked like she'd been practicing for this exact moment. I grabbed her hair and pushed deeper until she gagged.
"Fuck, that's it," I growled. "Suck your brother's dick the way you wrote about."
She moaned around me, spit running down her chin. I fucked her throat for a few minutes, then yanked her up and spun her around. I ripped the yoga pants down to her knees and bent her over the arm of the couch. Her pussy was soaked, glistening. I slapped her ass hard enough to leave a red handprint.
"You've been begging for this on the internet like a little slut," I said, lining up. "Now take it."
I slammed into her in one thrust. She cried out, pushing back against me. Her cunt was tight and hot, gripping me like it never wanted to let go. I pounded her hard, the couch creaking, her tits bouncing with every slap of my hips. She reached down and rubbed her clit while I drilled her.
"Harder," she gasped. "Fuck me like you own me."
I did. I grabbed her hips and railed her until she came, shaking and soaking my balls. Then I pulled out, flipped her onto her back on the floor, and shoved back inside. Her legs wrapped around me. I fucked her deep and slow for a minute, then fast again, watching her face twist with another orgasm.
When I was close I pulled out and stroked over her stomach and tits, painting her with thick ropes of cum. She rubbed it into her skin, eyes glassy.
We didn't stop there. That night I took her to her bedroom and fucked her again, this time with her riding me while she read her own Tumblr posts out loud. "I want him to cum inside me," she recited, voice shaking as she bounced on my cock. So I did. I flooded her pussy while she came again, clenching around me.
The rest of the weekend we barely left the house. I fucked her in the shower, against the kitchen counter, on the dining table with her legs over my shoulders. Every time she called me "brother" it made me harder. She kept checking her phone, posting little updates without names, and the notes on her blog exploded. People were eating it up, but none of them knew it was real now.
By Sunday night her pussy was puffy and used, leaking my cum every time she moved. We lay in her bed, her head on my chest, both of us sticky and satisfied.
"Don't delete the blog," I told her.
She smiled against my skin. "Never. It's how this all started."
We knew it was wrong. We knew we couldn't stop. And that made every thrust, every moan, every load I pumped into her even hotter. Tumblr had started it, but we were the ones finishing it, over and over, raw and filthy and exactly the way she had always wanted.
