Valentine's Day, February 14th, is celebrated much like home. The only exception being that the girl gives a gift to the guy and the guy does not return the favor until March 14th, White Day. On White Day the guy gives the girl a gift which is supposed to be more significant than the gift the girl gave on Valentine's Day. So...image store's displays for Valentine's Day staying up for extra long and getting extra big for White Day. A few days prior to White Day and Valentine's Day, the convenience stores are full of huge displays. They are not cheap either. Some of these items are almost $100!
Then comes Black Day. Black Day is April 14. If you did not give or receive a gift for the prior two holidays, this day is for you! This day is made to celebrate singlehood. Many single Koreans are caught eating jajangmyeon - noodles with black bean sauce. Ja jang myeon are Chinese noodles and when eating them you are supposed to mourn the fact that you are single.
I've also heard of random other love-related days on the 14th from Koreans. Supposedly Rose Day (I think May 14) among other obscure days are sometimes celebrated. It's obviously not important enough for me to figure out all these holidays. The big days are V-Day, White Day, and Black Day. By the way, don't give Hallmark and Hershey's this idea! I'd like to keep the commercial holidays at home limited to no more than there are now.