Here is the full list of all 27 Yomawari: Night Alone achievements.
Played a total of 50 hours
Collected all collectable items for your room
Completed the puzzle
Collected all items
Completed the radio
Picked up a trophy
Picked up the Big Bell
Kidnapped by Mr. Yomawari
Found the Tsuchinoko
Made an offering to Jizo Statues a total of 50 times
Collected all usable items
Opened Garbage Bags a total of 20 times
Stayed home for a total of 15 minutes
Talked to Sis a total of 12 times
Cleared Chapter 7
Kicked the can a total of 50 times
Cleared Chapter 6
Cleared Chapter 5
Cleared Chapter 4
Fed a cat
Cleared Chapter 3
Suffered a Game Over a total of 30 times
Cleared Chapter 2
Hid a total of 50 times
Played a total of 10 minutes without the flashlight on
Cleared Chapter 1
Cleared the opening