Kirk here with some almost-too-late (or made too-late-already?) information about Halloween events in Kumamoto. This page lists several events for today. The one at the top is pantomime performances at 2 and 4 today on the roof of the Sakuramachi Building (屋上サクラマチガーデン).
I should have sent this out earlier but I was just thinking “Today’s Halloween. I wonder if there are any related events in Kumamoto” and happened upon this after a little Googling.
Happy Halloween!