He slammed his sister against the glowing monitor, her short skirt already hiked up over her round ass. "You wanted this 3D shit to come alive, didn't you, sis?" he growled, yanking her panties aside. His thick cock sprang out, already leaking, and he shoved it straight into her dripping cunt without warning. She cried out, pushing back hard onto him, her walls clenching tight around every inch.
"Fuck yes, brother, give it to me raw," she hissed, gripping the desk as he pounded her from behind. The screen showed their own 3D models fucking in the same position, polygons stretching and jiggling with every thrust he copied in real life. He grabbed her hips, fingers digging in, slamming deep until his balls slapped her clit. She was soaked, juices running down her thighs while he fucked her like an animal.
He pulled out just long enough to spin her around and shove her to her knees.
"Suck your brother's cock," he ordered. She opened wide and took him to the back of her throat, gagging wetly as he face-fucked her. Spit dripped from her chin onto her tits. He reached down, pinching her nipples hard through her thin top until she moaned around his shaft.
When he couldn't take it anymore he hauled her up, bent her over the desk again, and drove back inside her pussy. The 3D models on screen mirrored them perfectly, her virtual ass rippling as his real cock stretched her open. "Deeper, fuck me deeper," she begged, and he obliged, pounding so hard the desk shook. Her orgasm hit fast and dirty, cunt pulsing and squirting around him while she screamed his name.
He didn't stop. He flipped her onto her back on the floor, hooked her legs over his shoulders, and fucked straight down into her. Sweat slicked their skin. Her tits bounced with every brutal thrust. "I'm gonna fill this incest cunt," he snarled, and she begged for it, nails raking his back. He came hard, pumping thick ropes of cum deep inside her, hips jerking until he was empty.
They lay there panting, the 3D animation still looping on the screen, their own bodies glistening with sweat and cum. She reached up, pulled him into a filthy kiss, and whispered, "Render round two." He was already getting hard again inside her.
