basement brothel

The day I started moving in to my new apartment, I noticed something strange. The apartment across the hall housed at least 2-3 Asian women who seemed to receive a lot of male visitors. In fact, on that first day, in a half hour span, two different middle-aged men knocked on the door and were let in.

Before I left for Australia, I commented to J that I thought they were prostitutes. He knows I enjoy making outlandish observations, but while I was in Australia, he had plenty of time to make his own observations. The trend continued. There seemed to be a steady flow of male visitors who would leave typically within an hour.

Every time there is a noise in the hallway, we go bolting to the peephole to see who might be out there. It never fails. It's always a random man. There have even been a few repeat visitors. We take every opportunity to peak into their apartment via the sliding glass doors in the back. There is a partition up on one side and a sofa bed, I believe. The tv will often be on, but nobody is there watching. I never see them inside, so I can only deduce that they are in the bedroom!

I'm tempted to knock on the door one day and introduce myself. I'm afraid the new neighbor window will be closed soon. How am I supposed to gather more evidence to support my hypothesis?