I've been with women with hardly no sensitivity in their nipples as I kissed/ licked/sucked/bit(gently!) to women whose nipples were rock hard straight away & groaned as they were stimulated nothing much hotter than that
my ex fiancee for e.g u could be stimulating her nipples sucking away for half an hour & she'd have no reaction
I always play with my sensitive nipples when pulling my mickey Do u have sensitive nipples?