As mentioned above, the Japanese came up with "White Day" [ホワイトデー] which takes place on the 14th of March. The day gives men a chance to give back white chocolates to the ladies who he received chocolates from - but! He has to make sure that what he gives costs more than what he received. Its hard to tell how much received chocolate costs so he ends up spending a bomb.
If the lady then receives chocolate from a man that was cheaper than what she gave, this can be seen as a case of sexual harassment!
Given all the chocolate marketing terms, White Day and a risk of sexual harassment if one does not spend enough, its no wonder why many folks think that Japanese Valentines day is a conspiracy by the chocolate industry.
20% of annual chocolate consumption in Japan takes place over the Valentines day period.

Ah, there is actually a "Orange Day" [オレンジデー] which takes place on the 14th of April.
Orange Day was introduced in 1994 and is a day where partners would give each other oranges to prove their love for each other - introduced as an excuse to sell more oranges.

Source: Dannychoo