Hips and buttocks are made up of three major tissues, bone, muscle and fat.
If you are past the age of 25, there is little you can do about your bone structure. Earlier than age 25, HRT will definitely give you the shape you want.
Muscle can be built up to the point where your gluteus maximus muscle can be significantly larger.
The real important thing is fat. Trim women have a body fat of about 20%. More than that tends to be placed on the outer thighs and buttocks. More than 30% body fat is too much. Expect to see this extra fat on your face, arms, tummy and breasts.
If you are exercising to the point of body fat less than 20%, you are not going to have enough fat for a typical female body. But you will look fantastic wearing high fashion clothing.
