Here is the full list of all 16 Aokana - there are Four Rhythms Across the Blue - there are EXTRA2 achievements.
View an FC Match in the Gallery
Get all Achievements
Fill the Sprite Viewer with 7 Shitou-kuns.
See the ending
Finish Chapter Seven
Finish Chapter Six
Gotta go fast
Finish Chapter Five
Witness the mother of all rice balls
Finish Chapter Four
Finish Chapter Three
Finish Chapter Two
Finish Chapter One
You had no business seeing those photos
Finish the Prologue
Launch the game for the first time