I can understand your discomfort. Bumps on thighs and buttocks can be very frustrating, uncomfortable, and discouraging. There are different type of skin problems that can cause the type of bumps that you are describing. These may include Acne Vulgaris
, or Keratosis Pilaris
The probable underlying causes might be a folliculitis or keratosis pilaris. Folliculitis is an irritation of the hair follicle by friction or chemical or bacterial infection. Keratosis Pilaris is a problem in which the hair follicles become trapped and plugged. This occurs on back, buttocks, and thighs.
By seeing your description the most probable cause might be Keratosis Pilaris. This is an inherited disease. This will be confirmed by seeing affected area of skin.
As this is not a harmful condition, it is better to follow the below things
1.Don't scratch at the bumps or rub your skin roughly.
2. Use warm water
3. use soap that has added oil or fat.
4. Use thick moisturizers
There is no specific treatment but moisturizing lotions or creams may help your skin look and feel better. There is no need to worry but follow the above aspects which can make your symptoms relieve soon. Hope you could understand all the aspects and act accordingly.