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.
You've had a sweet journey with the heroine, right?
Received the gift from the god of the mountain.
Found out the designer of the teahouse.
Meet with the manager.
Meet with the girl.
Here comes the heroine.
Congratulations! You found the secret bonus content!
To prove this, I clicked "Start Game".