area but I didn't paid them much attention. Recently, I noticed them were getting bigger. I've lost sensibility in that area and it's looking dark-reddish. I have them in both sides between my legs and now are about 2.5 x 0.2 inches and straight in the legs direction like veins or something.
I am wondering what can this be, it looks now completely different from how jock
area, then this is likely to be stretch marks. If you have lost weight rapidly in the past few months ,then stretch marks may be the likely diagnosis. This may not be something that you should be very worried about. You may apply some vitamin E cream over the area to help smoothen the skin. Drink plenty of water and exercise regularly. If these marks appear to increase in size or changes in appearance then you may need to have this assessed.