In the dim light of the closet, the siblings' bodies press together, their breathing ragged with anticipation. She can feel his heart pounding against her chest as he grinds his hips against hers. His hands roam her body, squeezing her ass, cupping her breasts, making her gasp. She reaches between them, wrapping her hand around his hard cock, stroking him until he's throbbing in her hand. He lifts her leg, positioning himself at her entrance. She's soaking, ready for him. He slides in, filling her completely. They move together, their bodies slapping together, their moans echoing in the confined space. It's intense, it's illicit, and it's everything they never knew they wanted.