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