In the sultry heat of an Argentine afternoon, I find my stepsister, Michelle, sprawled out on the bed, her big, natural tits heaving with each breath. I can't resist the temptation to fuck her tight, untouched cunt. She whimpers as I push my massive, unprotected cock into her, her pussy stretching to accommodate my size. I pound her hard, her big ass bouncing with each thrust. She squirms and moans, her pussy convulsing as she squirts all over my dick. I groan, filling her with my hot cum, marking her as mine.