Moll Buzzer Meaning

Example: A petty criminal who follows a pickpocket.
July 26, 1874, Chicago Daily Tribune
  Habitual criminal Molly Holbrook "has taken as her companion one Jim Hoya who is known to the police detectives as a 'moll buzzer,' a man who follows a female pickpocket about, and receives from her the 'leathers' taken from a woman in public gatherings."