I remember speaking to an enlisted Navy chief petty officer about three years ago while I was in San Diego.  He had some advice for me going into the navy that, although I don't think I would have to worry about needing it anyway being as that I am married, made for a good story.  He told me about how his ship pulled into port in Singapore and they all had liberty (free time to play in port for those non squibs).  This guy and his friends stepped off of their ship and noticed that there were beautiful women everywhere.  Naturally they all thought they had died and gone to heaven after being on a ship for months.  They had heard the stories and warnings about how if you want to get together with any of the women to do a "Crotch" test to make sure that they were women and not cross-dressers.  Anyway, this guy decided to play it safe and steer clear of the women.  On his way to explore the city one of his friends came up and introduced a girl he had met.  The guy took a look at the girl and noticed a scarf around her neck.  The temperature wasn't exactly cool, so it was a little out of place.  He took his friend aside and asked him if he had done the crotch test.  The guy replied, "No I know she's a girl, don't worry about it".  The guy insisted that he check just to be safe.  His friend replied, "fuck you man, I know she's legit.  Come on babe, we're out of here!"  The guy shrugged off his friend's rudeness and thought, "well maybe he's right and I was just being a prick."  The next day, the man was reporting back to his ship.  On his way to the harbor he spotted his friend sitting under a street lamp with his head between his knees.  He walked up and asked his friend if he was alright.  His friend replied, "I don't want to talk about it." The man then said, "You fucked a guy didn't you..." to which his friend replied, "I don't want to talk about it."  Moral of the story, either stay away from the locals in Singapore, or, at the very least, do a crotch test.