Hi. I Have Been Having A Reoccurring Spot On The

Hi. I have been having a reoccurring spot on the top of my butt Crack. It will clear up for months at a time and then come back. It usually starts getting raw then itchy then starts makingredients a blister like thing. Sometimes it's small and used to make a pimple and its.pop....usually when I run my finger over it hard while in a bath or w something itll bust blisters and crust over and dries out but still itches. It's always in same spot too. I haven't consulted a dr yet. Today it flared back up and had a strange smell. What could it be?