In my opinion, most people asking for vaginal sex with Amelie are confusing the story pace with the waiting times between each update.
If you play from start to finish right now you will notice that there isn't that much development between MC and her to justify vaginal sex. I would agree if we were talking about the older cousin.
However, if you take into consideration the release date to now then yeah, it feels like an eternity and I can see why people would ask Xenorav to rush things.
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