I must say the game doesn't support incest narrative very well.
Why even let player changes step-father's/uncle's relationship, if at the end the girls call him "my dad" and overall from dialog of all characters it doesn't match if you make him to your father as well.
I don't care much about it, but I wish it were better prepared for it before making him into MCs dad as well.
I just found the game, but my guess is that the support for the relationship change came much later.
There are even imagines that still say what they are.
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