Performed by adults in a stepsibling role-play. His two gorgeous new stepsisters constantly mock each other's breasts and demand that he choose a side. The small-breasted sister claims that large breasts are less sensitive and smaller ones feel more. Outraged, the busty sister tells their stepbrother to test her himself. As he fondles her, her breathing grows ragged and she becomes visibly aroused. Refusing to lose, the petite sister has him play with her nipples too, and their contest keeps escalating.