He wanted to see her again and gave her his phone number but she misplaced it.
'He said I did everything right,' she says wistfully.
Off-white bed sheets flap on the clothes line outside the few small ' work rooms' .
Chewing of betel nut is banned inside the premises and there's a regular to and fro of patrons through the large front gate as they take to the outside street to partake of the natural and traditional carcinogenic.
Greying, ill-fitting sheets barely cover the bed in one room, where a small bedside cabinet was empty except for eight condoms placed on top.
One such raid of the notorious Three Mile Guesthouse on a busy Friday night in 2004 hit international headlines due to the brutality of the police, who forced about 80 people on the premises to march for an hour through the streets to the Boroko police station.
With the ever-present threat of HIV/AIDS - the most recent reports suggest rates are increasing at almost 30 per cent year in parts of PNG - Bertha's safe sex advice could be the difference between life and death for vulnerable girls whose own families and loved ones have turned their backs on them.