As you know, Valentine’s day is originally from western countries.
Valentine’s day in Japan is different from the original. Women give ‘chocolate’ to the men they love on February 14th. The sales of chocolate is high before February 14th and we can buy many kinds of chocolate at stores for Valentine’s day. Now, people buy chocolate not only for lovers but also for friends and for enjoying by themselves.
It is said that Valentine’s day was imported by a Japanese chocolate company to Japan and became common in 1970’s. Chocolate makers were succeed to increase their sales!
Image search ‘Valentine’ with Google Japan
Image search ‘Valentine’ with Google US
You can see Valentine’s day has strong connection to chocolate in Japan.
Information about demand and supply of chocolate in Japan
Chocolate and Cocoa Association of Japan