Every 14th day of March “White Day” is celebrated in Japan. It is exactly celebrated one month after Valentine’s Day. White Day is considered to be a social obligation while Valentine’s Day is thought to be to be a romantic time.
The reason its called “White Day” is because the color of sugar (white) is the main ingredient for candy which was traditionally given on White Day – source Wikipedia.
This Japanese (and Korean) cultural event was started way back 1978, when they noticed that it was mostly men who bought chocolate on Valentine’s day, and then a unique fashion started women give the men gifts of chocolate as well as other gifts.