The main character is probably Klaus. Given the name of the story, it's a safe bet that the story revolves around him. He could be a regular person in an extraordinary situation, or perhaps he has some unique qualities that the story focuses on.
Well, without more context, it's hard to say precisely. It could be a story about Klaus's origin. Maybe he's a hero in a fictional world and the story details how he came to be, his family background, and the events that led to his becoming who he is in the story. For example, if it's a fantasy story, it could involve magic or special powers that Klaus discovers along the way.
Since I don't know the 'cecil original story' in detail, it's likely that the main character is Cecil himself.
The main character in the original marathon story was a Greek messenger.
The main character in the '127 Hours' original story is Aron Ralston.
I'm afraid I can't identify the main character in the 'ghazi original story' without more details. It could be that the main character is a Ghazi who has some special abilities or characteristics. He could be a leader, a seeker of truth, or a person with a unique mission. Maybe the story is told from his perspective, and his actions and decisions drive the plot forward, but this is all speculation without further knowledge of the story.
The main character in the original story of 'The Revenant' is Hugh Glass.
Since it's called the 'annie original story', the main character is likely Annie.
As we have limited information about the 'seraphina original story', we can only assume that if the story is named after a person, Seraphina would be the main focus. However, there could be other important characters as well that play significant roles in the story.
The main character in the Candyman original story is Daniel Robitaille.
As the story is named 'anastasi original story', it's highly likely that Anastasi is the central figure. She could be a real person that the story is based on, or a fictional character created for the purpose of the story.