Will I lose my hourglass figure doing the P90X?

So I am thinking of purchasing the P90X Instanity Workout to lose about 35 pounds. I am 18, 5"5, female and weight 146.I have an hourglass waist and I love it, but whenever I watch the infomercial videos, I see that the women are in great shape but have an ugly musclar body; it is a square waist with a four pack. I am not overqeight, but I just would like to get tone and not have cellulite on my thighs anymore.