Until fairly recently, Halloween was rarely celebrated in Japan.
True, Kiddyland in Harajuku began sponsoring a Halloween "parade" on Omotesando some 25 years ago, but it tended to be a small affair mostly participated in by expat families.
But a few years ago something happened.
Japanese parents started bringing their kids. Then Japanese people of all ages started showing up—in costume.
For the longest time, if you wanted Halloween-themed candies, you had to go to specialty shops like Sony Plaza and Tokyu Hands, which carried imports from the U.S. But mass market retailers and national brands have started to get in on the action.