Have you tried it? Do you like it? For many men, the nipples are hot-wired straight to the groin. And this isn’t a toll route.
If your partner is a nipple buff – or tit-torture addict – already he’ll probably let you know. In which case, follow his instructions.
If you haven’t yet explored (much) this highly sensitised body-bit, you need to make up for lost time!
With your partner, or alone, while masturbating, try licking (okay, that one will require your partner) or stroking first. See how that feels – and slip into that feeling. Get beyond any nerves or resistance you might have – and past the point where it’s simply ticklish.
Experiment with nibbles and pinches. Go progressively: warm each other up and see how much of a squeeze each other likes. There might come a point where pleasure and pain do become indistinguishable, but you’d be well advised not to head for that point straight away.
During full sex or oral and masturbatory play, if you want to surprise your partner with an un-warmed-up for pinch, wait till he’s moaning with pleasure, already lost in it, then you can (fairly safely) interpret the yelp or squeal to mean: ‘That felt good.’