@reasoning logic,
I did see your vid, thought it alright but it put me in mind of Sesame Street for some reason.
Halloween or Samhain, like Walpurgis Night or Beltane are two of the Sabbats observed by Pagans. Samhain is at the end of the year and is a non-day or extra day, because of the difference between the lunar and solar calendars. As it is 'a day that is not a day,' the boundaries between the real and spiritual worlds are blurred.
It's not about demons, that was used by Christian propagandists.
When Spendi mentions Walpugis Night he's referencing Bram Stoker's Dracula.