BlackDay,

Black Day (블랙데이) (April 14) is a South Korean informal tradition for single people to get together and eat jajangmyeon (noodles with black bean sauce).

The idea is that those who did not give or receive gifts on Valentine's Day (February 14) or White Day (March 14) can get together and eat jajangmyeon, white Korean noodles with black bean sauce, to celebrate their singlehood.