A thorough examination may be conducted in that way, and if you don't feel like it you may refuse it.
The doctor may have you undressed for "sex" related examination, like chancriod,gonorrhea, granuloma inguinal which were listed. Personally I believe it should be performed in a way of visual inspection, as it is deemed sufficient.
You may think the doctor has gone far beyond if there was a touch, especially "cupping" being involved.