I had been at work for about an hour when I felt a strong itch on the top of my right butt cheek...then another near my tailbone. By the end of my shift my entire butt inched like crazy. Got home, dropped my drawers, and both cheeks are covered in huge welts that look and itch like mosquito bites. No way did I get bit by one...I was wearing underwear and black pants AND a pullover type windbreaker jacket that I pull down over my butt. I don't sleep nude, either. The bumps are only on my butt cheeks except for 2 that are on my hip bone.