To further this confusion, while D cannot be a Stable Time Loop resolution to the game because of Homunculus's lack of opportunity for involvement, neither can any other ending, for similar reasons: In the others, Hugo is prevented from completing the loop. As he is sixteen at the time of his attempts on Eike's life, and it is revealed that his much older self is the one that finally finished a time machine to follow Eike with, Hugo needed to stick to his goal and live to that older age, so that his older self would actually finish making that time machine to hand to him, to start(?) this whole mess in the first place.
- In ending A, Hugo was taken somewhere else by Homunculus, who was then removed from the equation before he could reintroduce Hugo to the timeline. Result: No old Hugo in the timeline.
- In the B endings, Hugo is either killed, or dissuaded by a good fatherly smackdown, courtesy of Eckart Brum. Result: In the ending where Hugo lives, he's no longer set on revenge, and therefore doesn't make his time machine. In the ending he dies, well, he obviously doesn't build his time machine.
- In the C ending, he never reads his dad's notes, and thus never decides to go after Eike. Result: No time machine.
And in the EX endings, either Homunculus
is taken out of the equation
before he can get Eike to release him from the stone, and therefore the whole thing never happened, or
- Helena is cured, which means Dr. Wagner doesn't have a reason to become mournful and obsess on his studies, which would have turned to creating a life (Homunculus) and ultimately lead to his disappearance... and again, this means Hugo has no reason to hunt down poor Eike.