The room echoes with the wet, lewd sounds of their indulgence. The sister, her eyes glazed with lust, takes her brother's thick cock into her mouth, swirling her tongue around the sensitive head. He groans, his fingers tangling in her hair as she takes him deeper, her throat contracting around him. She can feel his pulse, his desire, as she sucks him hard, her hand working the length of his shaft. They're playing with fire, but they can't resist the heat, the taste, the taboo pleasure they find in each other's arms.