In Japan, some western cultural events are celebrated in a Japanese way. Valentines day is not an exception, it is celebrated quite differently, just like how Christmas is celebrated in Japan!
Valentines day in a Japan is a day for a woman to give gifts to men. Normally women make sweets and or buy gifts. Confectionery companies exploited it for commercial reasons to sell sweets, so women often get chocolates for her partner, or someone she fancies. Also, friends get chocolates for each other.
Valentines day in Japan is all about chocolates. Girls buy many sorts of chocolates from department stores. This season, department stores clear a special section (or even a whole floor) to sell chocolates and sweets. It will usually be full of girls buying chocolates.
In Japanese culture, Valentines day is a day to give gifts to your boyfriend, and also a day to show appreciation. Girls give chocolates to people at work as well. Some girls even get chocolates for their dads and friends will get chocolates for each other. It is almost like a chocolate giving day! Other than chocolates, some girls get marshmallows, biscuits or something sweet.
So when do girls get the gifts back.....??? Guys get gifts for girls on March 14th, a month after Valentines day. It is called White day and guys get chocolates, or get gifts or take girls out for meals.
Valentines are started as a committal reason, but it is sweet that people show appreciation to each other.