Greetings,Boils occur as a result of an infection around a hair follicle. They are common and are most often caused by the Staphylococcus aureus bacteria, the most common bacteria found on the skin. A staph infection on the inner thigh can cause a boil to appear, and become red, irritated, and painful.It can be treated with antibiotic topical sometime along with oral.,but without seeing the affected area can't say much and if you want me to give any personal advice you may can get in touch Regards