A nip slip can happen to any celebrity, especially the ones who frequently don bustiers and strategically placed ensembles of the risqué variety.
Once or twice...sure.
But Nicki Minaj is now the reigning queen of nip slips (Lady Gaga remains a close second), and there's just no explanation other than her boobs have developed a mind of their own and are struggling to break free of an oppressive, stifling system. Or...
The "Anaconda" artist just doesn't give a damn and may even kinda like the attention that comes with her nipples popping out of her costumes on stage, on the red carpet, on TV, Instagram...etc.