SPOILER ALERT:

yes, close, he replaces the guy. (its technically impossible for it to replace the girl with how that scenes done) but you're right, you catch a glimpse of him towards the end. Partly to let you know that boy is the same boy you play as 8 years later in the main story, Partly to symbolize for how long the Darkness has been there. Thats certainly not his origin, but hes there.  I can also say, that's not the only time Dark man can be seen hiding in the scene.....I appreciate you reporting this, but its all good. i did/do my best to build an experience with layers, for players who want that from there game. i do my best to make a rich game so its worth people investing there time, which leads me to once again, if i haven't already say, thank you for playing my game :)