I have a quick question about this specific jig.

Outside of school I have no problem number-closing, but inside it's a bit difficult for me. Most of the time the girls I want to number close are constantly surrounded by at least 5 other female friends, and they hang out in high-traffic areas (e.g. chow hall).

From what I've read and been told here, girls will go to great lengths to protect their image from the slut label - in my case, turning down a date that they would've, in private circumstances, agreed on, to avoid being seen as easy. Most of the times I find myself in conversation with girls but unable to number close because of these factors. Any help / tips on pulling this off?