I'm not sure specifically which 'behind the green door story' you mean. There could be various stories with this title. It might be about a mystery or an adventure that occurs behind a green door.
Since I don't have the details of 'behind the green door short story', it could be about a variety of things. It might be a story of a person who is curious about what lies behind the green door. This could lead to encounters with strange characters or situations. For example, it could be a portal to a different world, or it could hold a long - lost secret of the character's family. And as the character steps through the door, they are faced with a series of challenges that they must overcome.
There's no way to determine the main characters without more details about the story. However, common character types in such stories could be a curious child who is drawn to the green door, or a detective - like figure trying to solve a mystery related to what's behind the door.
Not having read the story, the main characters in 'behind the green door short story' could be many things. Maybe it's a detective - like character who is investigating the strange happenings around the green door. Or it could be a child who has an overactive imagination and the green door is part of their fantasy world come to life. There could also be a caretaker of the place where the green door is located, who has their own secrets and stories related to the door.
Most likely, it isn't a true story. Usually, such titles are works of imagination or literary inventions rather than recounting actual happenings. Maybe it takes inspiration from various elements but doesn't represent a factual account.
Perhaps it's the story of a great discovery. An alchemist might have been secretly working in that room. He was on the verge of finding the philosopher's stone. His experiments, his hopes, and his failures are all there. The room could be filled with strange apparatuses and half - completed elixirs, waiting for someone to uncover the mystery.
The 'behind the door short story' could be about mystery. Maybe there is something hidden or unexpected behind the door. It might involve a character's discovery of a secret, like a hidden treasure or a long - forgotten message.