Here's the story on Japanese Christmas for you.
A first time visitor to Japan during the November, December months would have the impression that Japan is a predominantly Christian country. This destroys their preconceived notions that Japanese are Buddhists or Shintoists, who don't wear their religion on their sleeves. I too, was very close to being deceived by the Christmas fervour I saw in my first year in Japan, back in the 20th century.
A recent query on Japanese Christians made me think of it again. So, I
did some extensive research on Christianity in Japan. This basically consisted
of the following question I asked my wife. "Yo, when did Christmas
become so big in Japan?" She was not sure, but thinks that it might
be after the war. That cleared up a lot of stuff and helped me complete
my research paper.
Jesus Christ, sorry, Christmas was born in Japan a few decades ago, in the latter half of 20th century, just after the 2nd world war. The facts behind its origins are lost in the labyrinths of history. Over the years, after many retellings and modifications, what has remained with the Japanese people is the essence of Christmas as interpreted by the Japanese. For instance, Jesus Christ is nowhere in the picture. Not many people here associate Christmas with Jesus Christ. They probably have never heard of such a person. If you dig deep enough, you may be able to find a tenuous link to the conception part. It has got nothing to do with the immaculate thingy the scriptures say, but more of a practical activity that precedes it. More on this later.
Let me explain about the festival itself. The celebrations start around November, when, in a perfectly synchronized move as can happen only in Japan, all the shops, department stores, supermarkets, noodle shops, anybody selling anything from underwear to indecent toys, start playing Christmas jingles and decorate their places with Santa and other such motifs (nowhere would you be able to see anything remotely connected to the poor guy who was supposed to have been born on Christmas day.) Here, Santa is the most important character in this consumerist orgy. Perhaps they think it's Santa's birthday. Anyway, the season is officially on from November and people start buying presents and cakes and generally have fun at the malls and shops across the nation listening to the same old jingles.... "Santa Claus is XXXX-ing the town." Big Christmas trees go up in all the major towns and fashions spots. Many are indoors and are made of plastic. People, especially couples, actually go to see them and take pictures of and with them.
You must have noticed the stress on couples. On Christmas Eve, Japanese lovers (in proper as well as adulterous relationships) go for romantic dates and dinners. This is where the tenuous link I mentioned earlier comes in.
Everybody knows that urban Japan has a space problem. People live in cramped abodes with little or no privacy. Young lovers, as you all know, need a bit of privacy. This is cited as one of the reasons for the proliferation of something euphemistically known as love hotels. A "love hotel" is slightly different from normal hotels. It is a very discreet place where you can rent rooms for a few hours and do fun activities, which otherwise maybe a bit uncomfortable doing inside cars or park benches in the night.
Well, the lovers, enjoy romantic dinners and walks and Christmas trees and stuff and a few of them eventually decide, convince or force their partner to go to one of the aforementioned establishments conveniently located in back alleys or near highways for a brief period of fun and frolic. If they're employed people, they'll hurry up and try to catch the last train home, because they have to work the next day, as Christmas is a regular working day in Japan. This is the impression of Christmas you get after you spend a few years here.
P.S: There are many legit Christians around in Japan, who probably celebrate Christmas in a different way. Christianity came to Japan with Francis Xavier, the guy whose mummy (not momma, but the mummified body) is kept in a Goan church for the last 400 years. However, the Shoguns didn't allow it (Christianity, not the mummy) to spread and killed quite a few in coastal cities like Nagasaki etc who were involved in such activities. Some did stay as hidden Christians. Nowadays, there are no restrictions. The Christians probably number less than 1% of the population.