Quick Answer
Whole Wheat Flour does not use the same grams-to-cups value as every other ingredient. Using a practical US cup reference, 120 grams of whole wheat flour is about 1 cup.
That means 100 grams of whole wheat flour is about 0.83 cups, while 200 grams is about 1.67 cups.
Whole wheat flour is denser than cake flour but lighter than bread flour due to its bran and germ content.