Locked in their shared bedroom, the siblings can't resist their mutual attraction. The sister, dressed in a thin nightgown, can't ignore her brother's bulge tenting his pajama pants. She straddles him, feeling his hardness through the fabric. He groans, grabbing her ass and pulling her closer. She grinds against him, her pussy growing wetter by the second. He pushes up her nightgown, exposing her bare breasts. He cups them, thumbing her nipples until they're hard peaks. She unties her gown, allowing it to fall open, revealing her smooth, shaved pussy. She guides his hand between her legs, and he fingers her, feeling her slick heat. She moans, riding his hand, her juices coating his fingers. He lifts her, positioning her over his cock. She sinks down, taking him deep inside her. They fuck slowly, their bodies pressed together, their breaths coming in sync. She leans back, riding him Reverse Cowgirl, her tits bouncing as he thrusts up into her. She comes with a cry, her pussy clenching around him. He follows, filling her with his hot cum.