When the ‘why does it matter how many guys she’s slept with’ argument comes up from a girl. This is what you should do:
Ask her if it’s okay to sleep around when your going out with a guy – if she says no, ask her why does it matter
how man guys she sleeps with?
What she doesn’t get is both have someone she cares about opinion of her down graded. (unlike the opposite). Then pump and dump her.
If she says yes, just pump and dump her.