In the dim light of the closet, the siblings' hands explore, learning each other's bodies with tentative, curious touches. He traces her curves, pausing at her breasts, feeling her nipples harden under his touch. She wraps her hand around his cock, stroking it to full hardness, her eyes wide with wonder at the power she holds. They sink to the floor, legs entwined, their kisses growing more urgent, more demanding. She straddles him, guiding him inside her, gasping as he fills her. They move together, lost in the rhythm, until they shatter, their cries muffled by the closet walls, their bodies slick with sweat and sin.