All the main characters in the book believe in ghosts, so it's merely natural for this one to be there.
Early in the game, the characters believe that Lavos created the time Gates.
This presupposes that "the main character believed in God".
This eventually led to revolt and, some characters believe, destruction of the entire continent.
The main character, the monster Dennis, believes that human children are under his bed and will get him as he falls asleep.
A character who, rather awkwardly for me, doesn't herself believe in the concept of character.
Other character of the series, Ciachciarachciach, believes in his telekinetic powers.
Scenes would often continue after the characters believed the cameras were turned off.
The characters believe that damnation follows suicide for the victims.
The character believes that the only way to achieve these goals is through Mordred, whom he sees as an opportunity to further his plans.