The fourth and final installment of the hugely popular "MILK Junkie" series! Three girls enter the "Big Boobs Grand Prix," a competition to find the girl with the biggest breasts in the world, all in an effort to have the protagonist, Wataru, all to themselves. Even during the contest, they sneak off to have some thrilling, sexy encounters with Wataru... This time too, big boobs and massive breasts are all mixed together and jiggling! Who will win the coveted "Big Boobs Grand Prix" crown? And who will finally win Wataru's heart...?