It was started by a chocolate company called Mary Chocolate, and after that, all the other chocolate companies copied with a catch phrase “women give chocolates to men”. Of course this custom originally came from abroad , but it has become popular in Japan too.

Also, both Valentine’s Day and White Day gifts can be given to not only your loved ones but also to your friends or workmates.
I think it is an interesting but unique event.
Don’t be surprised if you are a man and get chocolates on Valentine’s Day.