@Novakane - yeah, I believe that is the item. Still haven't figured out how to get one....I've danced for hours in JP Central plaza and nada. :( The translated site I saw has the following info:
"Trick or Treat" challenge
Say hello to the people around will get a challenge from Hell enjoy dancing!
※ The dance must be done around the middle of the pumpkin.
Please join together near the middle of the home square.
Wonderful if we could satisfy the inhabitants of Hell, Hades Great Satan will give a reward to everyone behaved themselves.
Yeah, not getting anywhere with this one...
UPDATE: Ok, I'm slow. You posted a schedule of times -- I did a search on google for "time in japan" to see what time it is there. The event times are so spread out -- that probably explains why I haven't managed to score anything. Looks like next event is around 1.5 hrs away from the time of this posting -- will give everyone a head's up if I get anything.
Here's a link to make things much easier. It gives the exact amount of minutes before the next event starts. I finally managed to attend one and got the reward (the little light up pumpkin). The event itself was cool to watch. Make sure you dance too! Here's a video of it from youtube: