Answer:
The relationship between Lord of the Flies and the Beast is fear. Both created fears in the minds of the kids and it resulted in chaos. It is while trying to confront the beast they became savages
The central idea is the same as the main idea. Most of the time, the main idea is mentioned in the Title. Without reading the essay, I do not know what the central/main idea is.
I believe the answer could be found in a file but 72737 sound correct hahaha