Not to be judgmental, but... weird.

Seriously, though, I've not seen that before, and I don't think I've heard of it either. But I know I have very different behavior on different parts of my body. When I first shaved everything (i.e., arms, torso, legs, etc), I had no problems at all on my lower legs or armpits (aside from my clumsy shaving cuts), very minor red bumps here and there on my arms, a smattering of them on my chest, and pretty thick mottling on my upper legs and bikini area. I just continued doing what I was doing, adding pretty aggressive exfoliation and not shaving areas that were mostly red until they cooled off, and now almost everything is happy again. Just a few spots on my upper legs left, and I think they're fading.