If you happened to be walking around Hongdae on Saturday night, you may have stumbled across some rather gruesome looking fellows who were participating in a so called "Zombie Walk". From what I learned from talking to some of the participants, it was a rather loosely organized group of foreigners who decided to dress as zombies and walk about Seoul and see people's reactions.
I guess they rode the subway, walking through subway cars in a very zombie like manner. Not surprisingly, one guy called the police (who told them to not make too much noise because they weren't really doing anything against the law) and another ajosshi punched one of the zombies in the stomach and kicked him. But, everyone was in good spirits and ready for an evening of haunting in Hongdae when I found them. Korean reactions were varied, but my favorite was the girl who shouted "So cute!" when she saw one of the zombies and proceeded to hug him.
All in all, seemed like a fun time for zombies and victims alike.