First things first: All these not only locking whenever you start a new game (meaning you can never have all unlocked), but also being fucking QR links to a perpetually overworked server is complete nonsense. That being said, these guys know their way around a renderer.
Going off of Lymmeln's post, here's a preliminary list of unlocked scenes.
SCENES
Maia:
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You must be registered to see the links
You must be registered to see the links
Orgy:
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You must be registered to see the links
You must be registered to see the links
Rita:
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You must be registered to see the links
You must be registered to see the links
Achievements:
Row 1:
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(Maia Foreplay)
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Digging Out The Mole
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(Orgy Foreplay)
Row 2:
Loot Hoarder
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Magic Fingers
Daredevil
Row 3:
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The Spy Among Us
Ultimate Charmer
I Did it For Science!
Row 4:
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(Do mixing puzzle on first try and fast)
?
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(Get all conversations in a single playthrough)
?
Preliminary gift info from Chii:
Necklace: Lucy (Manager)
Box of chocolates: Mia (Bartender)
Vodka: Rita (Lab girl)
Mail reward thing: Kyoko (Receptionist)
...which would leave the panda as the gift for Andrea (Secretary)
Door code: 49517