Here is the full list of all 27 The Crooked Man achievements.
Get Game Over once
Survive first encounter with the Crooked Man
Read the books in the hotel library
Finish the Prologue
Go back to bed without answering the phone
Get Game Over 5 times
Defeat the Crooked Man in Scene 1 without taking any damage
Get Bad Ending 1
Finish Scene 1
Read the books in the school
Get killed by poison gas
Escape the gas with over 1 minute to spare
Try to enter D's bed
Try to enter the bed next to D's bed
Get Bad Ending 2
Defeat the Crooked Man in Scene 2 without taking any damage
Finish Scene 2
Read the books in the hospital day-room
Don't miss a single shot at the Crooked Man
You shot Fluffy
Finish Scene 3
Get Bad Ending 3
Get Bad Ending 4
Finish Scene 4
Beat the game without drinking the energy drink
Beat the game once
Beat the game twice