In the confines of their beat-up car, these siblings can't resist the temptation of each other's bodies. The sister, her heart pounding with excitement and fear, reaches over and feels her brother's throbbing erection through his jeans. She unzips him, revealing his hard, twitching cock. He hisses as she takes him into her mouth, her tongue swirling around his sensitive tip. She bobs her head, taking him deeper with each thrust, her large breasts bouncing against his thigh. He can't help but grab her hair, guiding her as he fucks her mouth, their moans echoing in the small space.