I'd like to start off with I have not finished the game.
So. Eugene's parents. They are ether out of the picture, such as he got emancipated or something. Or maybe they put him in that apartment and just pay his bills when they live in a different house. This could be due to his parents divorce or a death in the family. Or they are extremely neglective to him.
They might also just always be at work or something but he skipped school and I'm pretty sure that they would have shown up or something to lecture him or something, because of they didn't I get the impression that this is not the case.
Update:
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