Here is the full list of all 15 She and the Light Bearer achievements.
collected all light bearers in credit scene
scared orchid with snail
slapped by mushroom 10 times
completed chapter 5
completed chapter 4
witnessed mushroom sacrifice
completed chapter 3
collected all snails
used cucumber on potato
answered all riddles
completed chapter 2
completed light 'n orb test
completed chapter 1
found all secret carvings
all achievement