There comes a time when every sub loses their focus, becomes distracted with things and that lack of concentration and control creates a cloud of angst within and around the sub.
The sub is cranky, grumpy, frumpy and in these moments of childish brooding can outwardly display this through the Domme's choice of attire.
The period panties, designed to hide messes, the sub's irrational emotional outbursts are well encumbered in a nice dark pair of thick cotton panties.
