Most likely, the main character is the man in the wall. He could be a victim, like if he was wrongly trapped in the wall. Or he could be a more sinister figure, depending on the nature of the story. Maybe he has some special powers or a dark past that makes him an interesting main character.
Since I don't know the specific story, the main character is presumably the man in the wall. He is likely the focus of the story, and whatever events or situations are described probably revolve around him.
If it's a horror - type 'man in the wall story', the main character could be the person who discovers the man in the wall. This character would be the one experiencing the fear and trying to figure out what's going on.
Not having read 'the man in the wall short story', it's hard to be definite. However, we know there's the man in the wall. There may be characters like a child who discovers the man in the wall and then tells their parents, which could lead to a series of events. Or there could be an old wise person in the story who has some knowledge about the wall and the man, and tries to offer advice or help regarding the situation.
Since we don't really know the specific 'woman in the wall story', it's hard to say for sure. But it's likely the woman herself is the main character.
As the details of the 'girl in the wall story' are not clear, it's difficult to determine the main character precisely. However, if it follows the common idea of a girl being in a wall, she would be the main focus. She could be a young girl with a unique backstory, like she was put there by some villain, or she ended up there by accident while exploring an old building. The story would likely revolve around her experiences and how she either gets out or what her purpose is while being in that situation.
Since I don't know the exact story, if it's a typical horror or mystery story, the main character could be the person who discovers the woman in the wall.
Since we don't have much information about the story, it could be anyone. It might be a fictional character created for the story, like a wandering minstrel who decides to take a break on the wall. Or it could be an ordinary person from the neighborhood, just looking for a quiet place to be.
Since I don't have the exact content of 'the man in the wall short story', I can only guess. It could be that the man in the wall has a unique ability or knowledge related to the wall. Maybe he's a guardian of the wall, or the wall holds some secrets that only he knows. The story might unfold as he reveals these secrets to others, or as others try to find out what he knows about the wall.
As we don't know the details of 'the man story', the main character is simply 'the man' in question.
The main characters of " On the Wall " included Li Qianjin and Pei Shaojun.
I'm not sure who the main characters are in the 'War of the Wall Story' as I don't have more context. It could be leaders of the opposing sides in the war over the wall, or ordinary people who are affected by the wall and take a stand.