Receptionists on Woosung Street (吳松街)

What were these ladies doing at 6 AM on dirty Woosung Street, one block away from Temple Street? Each was sitting strategically at the base of a staircase leading up. If a man should appear to be looking for something as he walked by the older lady with a fan, she would inform the man that there were ladies offering certain services upstairs. I am not so sure about the younger lady. For some reason they all used to be old ladies with fans.