Here is the full list of all 8 Shan Gui achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Congratulations! You found the secret bonus content!
You've had a sweet journey with the heroine, right?
Received the gift from the god of the mountain.
Meet with the manager.
Found out the designer of the teahouse.
Meet with the girl.
Here comes the heroine.
To prove this, I clicked "Start Game".