Korean men tend to swear a lot. I have this friend who grew up in Pusan area. Normally, he talks like others, but when he relaxes, he uses foul language that will make sailors pale. In few occasions, I have heard him talk with a friend he grew up with in Pusan and their conversation was amazing enough for me to wonder it could be bottled and sold as paint remover. It didn't last more than five minutes but whole lot of killing, raping, castrating, and even cannibalism was used in a weird ritual of male bonding.
This is not limited to Korea nor others. There was this executive level guy who was in habit of using foul language in the office and made the mistake of directing four-letter words to me. I knew he really meant to say "Nice to see ya again", but it came out like "How's the bloodsucking biz, c**ksucker." So I responded in the same language, "I see that you didn't get fired yet, a**hole." Then he and I both grinned and shook hands. Of course, people standing around us were a bit shocked, but I think they understood that there was little prospect of a fist fight breaking out.
What is the lesson here? Well, let's just say there are languages and then there are lingos. It might be fun to designated one day out of a month as Foulmouth Day for bloggers.