It's hard to tell without reading the story. However, the main character could be someone with a special ability to see or communicate with the ghost. And the pleading ghost is another main character. Maybe there are some antagonists as well, like people who don't believe in the ghost's plea and try to stop the protagonist from helping the ghost.
Since I don't know the details of the story, I can't say for sure. It could be the ghost itself as one of the main characters, and perhaps the person or people the ghost is pleading to.
Well, it could be a story where the ghost has a plea related to its past life. Maybe it was wrongly accused or killed, and in the afterlife as a ghost, it's pleading for the truth to be known. It could also be pleading for someone to help it pass on to the other side, perhaps because it's stuck in a limbo between the living and the dead due to some unresolved issues.
As I don't know the particular '1930 ghost story', it could have a protagonist like a young journalist who is investigating the strange happenings. There might also be an old caretaker of the haunted place who has some secrets.
In 'the ghost story', the main characters could be the people who encounter the ghost. Maybe a group of curious kids or a brave investigator.
The main character in the Ghost of Tsushima main story is Jin Sakai, a samurai with a strong sense of duty towards his homeland. His uncle, Lord Shimura, is an important part of the story. Lord Shimura represents the traditional samurai values. Another important character is Yuna. She is a thief - turned - ally of Jin. She has her own skills and knowledge of the island which prove invaluable to Jin in his fight against the Mongols. There are also Mongol characters like Khotun Khan, who serves as the main antagonist, driving the conflict in the story.
Well, it could be a variety of characters depending on the specific ghost story. Sometimes it's a brave investigator, or maybe a haunted family member.
The main characters include Ning Caichen, a young scholar, and Nie Xiaoqian, a beautiful ghost.
Often, there is a protagonist who stumbles upon the haunted situation. It could be a young person exploring an old place. And then there might be a secondary character, like an old caretaker who warns the protagonist about the ghost.
In a 'ghost of perdition story', the main characters might include the ghost which is the central figure of this tale of perdition. There could also be a medium or a psychic who tries to communicate with the ghost to understand its plight. Another possible main character could be a local who has some knowledge about the history behind the appearance of this ghost, and they play a role in either helping to solve the mystery of the ghost or getting in the way of those who are trying to deal with it.
In a Spongebob ghost story, the main characters are Spongebob, Patrick, and Squidward. Spongebob is the heart of the story, his enthusiasm and fearlessness (even when he's actually scared) drive the plot forward. Patrick is there for comedic relief, his cluelessness making the situations even more absurd. Squidward is important as he provides the voice of reason and the 'get me out of here' attitude. They are the ones who will experience the spooky events, get scared, and hopefully solve the mystery of the ghost in Bikini Bottom.
Since I don't know the details of this 'ghost kanan story', I can't say for sure who the main characters are. But surely, Kanan, the ghost, is likely to be one of the main characters.