It took me a while to realize that, if you look closely at the earlier episodes, this same shadowy figure is seen hiding around the scenes as an easter egg:
Episode 1 (Panel 2, top right corner, behind the steel mug):
Episode 2 (Panel 1, behind the grass, to the bottom-right of the speech bubble):
Episode 3 (Panel 3, behind the grass, under the speech bubble):
Episode 4 (Panel 4, behind a rock, to the right of the speech bubble, although not that visible):
Episode 5 (Panel 4, behind a tree, to the bottom-right of the speech bubble):
Episode 8 (Panel 2, behind a tree, under the N in 'YAWN!', although not that visible):
Episode 9 (Panel 1, on top of the tree stump):
He was not in these episodes originally, but it seems that Matthew decided to add him as a way to foreshadow the events in the coming threads...
