I know some genuinely nice girls who can put on a bitch shield when out in clubs. They do it without realising. It's a necessary strategy for a pretty girl otherwise they'd have weird guys following them around all night.

I find a lighthearted playful neg tells them you're not going to be messed with. Remain unaffected by their attempted 'shoot-down'. This instantly shows confidence that 99% of men don't portray.