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To get the "Meet the Demon" achievement, you'll find a secret ending by messing up with everyone you meet.
For "Night Saved", you can't get a single Surigram EXCEPT for Charlie's.
As for the "Good Ending" it's very specific:
Get Elliot's Surigram
Mess up with Bjork
Piss off Nulva
Get Joan's Surigram
Mess up with Sydney, Tobias, and Bernat
And lastly, get Charlie's Surigram.