"Originally, Halloween was a holiday where the barriers between the living and the dead vanish. Spirits cross the lands and people wear costumes to trick the spirits and appear friendly." Yoshiko's voice is dropping to a lower tone as she strikes a pose and tries to look very spooky.

"That's why there's trick or treat! The spirits would descend upon the realm and you had to appease them with candy, otherwise they'd mess things up for everybody."

This may or may not be bullshit.