Supposedly it's Christmas but it really doesn't feel like it. Christmas in Japan is basically Valentines day. Most couples go out to dinner, exchange gifts and then all the hotels are booked for the night or so I'm told. Otherwise there are some Christmas decorations up at many stores but as I'm working now I don't have time to shop so I've seen very few this year. Today, Christmas Eve and tomorrow Christmas Day are just regular work days in Japan.
The other thing they do is eat a cake. Where that tradition came from I have no idea but every other store and restaurant in Japan sells Christmas cakes. They are generally some kind of white cake with white frosting and strawberries. You can reserve them in advance. Even 7/11 and all the other convenience stores have them.
So, Merry Christmas.