In Japan, 2/14 is widely recognized as a day when women give chocolates to men, but 9/14 serves the opposite purpose. This day was chosen by the Japan Body Fashion Federation in 1991 as a day for men to give underwear to women with gratitude and love. The reason why the date, which falls between Valentine's Day and White Day, was chosen was influenced by the idea of "six months later".

The trend of women giving chocolates to men on Valentine's Day and returning the favor on White Day was already established. However, to further evolve this culture of giving back, "Men's Valentine's Day" was born. It was thought that by giving underwear as a gift from a man to a woman, it was possible to express even deeper affection and gratitude.
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