To become a game plot master you must write or submit a complete short story or your game plot (game story) more like a mini novel. Moderators will review your application and decide if you are eligible to become a GPM
A GPM (game plot master is not a forum moderator, he is only a game moderator hence he is not an official staff. If he abuse the guidelines members can report and the game master will be removed of his GPM status and grouped as regular member. Which he can only play and not moderate the game.
A GPM can edit delete remove post as he see fit according to game storyline.
He has control over the game play and not the members, or players.