My back and the bottom of my feet.
It seems that no matter when I shave or what I shave with, I always have two problem areas that require a touch up to be totally smooth. One is on the right/topside of my head (back where a part would end) and this big crease in the back of my head. Both take extra work to remove the stubble and get totally smoothness. I was just wondering what other bros might be having similar problems and what are your problem areas when seeking the perfect slyness?