The Two Sisters On Bancroft Lane

On a warm humid Houston night Thomas Mortensen, a young man of seventeen, is out for a walk. It's a familiar journey,

one he has taken several times before. But this night will prove far different from those in the past when Thomas comes upon a purse partially hidden by debris from the previous day's storm. He checks the contents and to his amazement finds it contains $150,000. He then realizes he has seen the purse many times and that the owner is one of The Two Sisters On Bancroft Lane. He does the noble thing by returning the money and purse to it's rightful owner. But, why after the good deed is completed, is he thrust into the danger of losing his life at the hands of the Two Sisters On Bancroft Lane and others? Why?