It's true that we don't write someone's name in a red letters in Korea. It is like unwritten law and Korean custom. If you do this to your Korean friend, he or she will think you are rude or offend him or her. Usually, when someone die, we draw the red line horizontally on one's name in Korea.

Hallo. It is true we do not write someone's name in red, even though we know its a superstition. There are some speculations about the origin but the most trustful one is, that it was banned because writing one's name in red was only allowed for emperor in old chinese society. (And it's true we've got some chinese influence in some parts of our culture) Nowadays, whatever the origin is, Korean people commonly say "if you write one's name in red, that will shorten the person's life." I hope it helps.

There are some theories about it, one that I find it convincing is that in the old times red color is used by shamans to deal with the dead(especially evil spirits). So we've been told that red color isn't right for a human being's name, but you know what? We use red ink when stamping our seal!

So there are quite a few Koreans that take superstition seriously?

I hate it > < But When I was in the US .. People kept wrote my name in red . So I was kinda paranoid