It was a unseasonibly hot day in the city as Emily was jogging through the city, Emily had a cute tennis outfit on with ubercute tube socks and green and orange Reebok tennis sneakers. Emily drank some cola when she began to grow, Emily had become a giantess, seconds later, the giantess Mariah crushed her way to the city wearing a basketball outfit topped off with Adidas basketball shoes and hot pink socks "I Challenge You, giant Emily!" said Mariah! "Under one stipulation!" said Emily

What is the stipulation?