The siblings' breathing grows ragged as they continue to grind against each other, their bodies slick with sweat. The brother's cock is rock hard, pressing insistently against his sister's thigh. She reaches down, wrapping her hand around him and stroking him slowly. He groans, his hips jerking forward as he fucks her fist, his release imminent. But they're interrupted by a noise outside the closet, a harsh reminder of the world beyond their forbidden haven. They freeze, hearts pounding, as the moment passes and they're left to wonder what might have been.