Once the number of sexually active girls in a group passes a threshold, then girls who DON’T have sex find themselves at a competitive disadvantage as far as attracting male attention. Then most of the girls will go along with the group dynamics.
It used to be that girls would “slut shame” other girls, for just that reason.
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What utter horse manure. I never had a problem attracting guys and I never put out.
That was then. I'm talking about now.