I'm 23 and wear thongs basically everyday. (Yes, I know all the things about how thongs can affect your lady bits) I was wondering if anyone had noticed darkening on the cheeks, but in their butt crack (I'm not sure of a more polite way to say that. Lol) and what could be the cause? Or how to reverse it. Maybe is it a thong being in there constantly rubbing the skin.. idk. It makes me feel gross, so I just want to figure out what it is. **Edited to add: no pain, bumps, itching or anything of that nature. Just darker skin.