The big clinical question is whether there are any perceived skin changes associated with this feeling. Meaning is there any type of rash, skin eruption, skin breakdown. Clearly if this does manifest then some type of dermatologic disorder is most likely the cause of your problem. This can include both infectious and noninfectious. From an infectious standpoint, the most likely cause is a fungal infection or athlete's foot they can be readily treated with many over-the-counter topical antifungals. Noninfectious disorders can include areas of eczema, contact dermatitis, psoriasis. These disorders may be best treated with a topical steroid. If it is simply drying out of the skin then a good skin lotion or emollient may be warranted. If there are no overlying skin changes then we must consider other systems that may be prompting the sensation of a raw feeling and numbness. Most likely this is some type of neuropathic process. Given the focal nature as described without any evidence of radiating type presentation both into the leg or distally into the foot this may simply present as a compression irritation of nerve distributing into this area.