Hi well come to HCM.
You may take high protein, fatty diet, reach in carbohydrate
,fruits rich in calori. Do
not do exercise in over.All this can help you to gain wt and along with your butt will
grow prapotionately but speicific distribution to Butt if you wish is not possible with
diet only. For that you have to contact plastic surgeon who can help uou by some cosmatic surgery.Thanks