The mysterious figure seen at the end of Petscop 4. Near the end of the video, the figure was slightly visible, however, when Paul moves closer to the right to end the video, the figure fled into the darkness.
Has many similarities to the player character. Appears to maybe wear a hat and has the same walking animation as the player character. This character may be someone we already know, but for now we will assume it is an entirely separate character.
Since the mystery man moves similar to the Quitter, it could be her, or just another unseen-as-of-now character that also follows the players movements.
There is a debate as to whether Mystery Man is the same person as the Shadow Monster Man. Some believe they are two separate people due to the complete lack of color or texture on the Shadow Monster Man. Mystery Man is clearly not a silhouette like Shadow Monster Man. Until we can come up with a reason why he would have color and texture in Petscop 4, and have no color in Petscop 6, some think it makes sense to consider them separate entities. The shape of their heads may or may not be different, as the image of Mystery Man is heavily compressed due to the darkness of the original video.