Here is the full list of all 30 East Tower - there are Kuon achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
You've unlocked all of the Achievements!
You've unlocked all of the CGs!
You've got the Bad Ending!
You've got the Normal Ending!
You've got the Love Ending!
You've cleared the Prologue!
You've cleared the Re-Prologue!
You've cleared Stage 1 and done a good job!
You've cleared Stage 1 and done an excellent job!
You've cleared Stage 2 and done a excellent job!
You've cleared Stage 3 and done an excellent job!
You've cleared Stage 4 and done an excellent job!
You've cleared Re-Stage 1 and done a good job!
You've cleared Re-Stage 1 and done a excellent job!
You've cleared Re-Stage 2 and done a good job!
You've cleared Re-Stage 2 and done a excellent job!
You've cleared Re-Stage 3 and done a good job!
You've cleared Re-Stage 3 and done a excellent job!
You've cleared Re-Stage 4 and done a good job!
You've cleared Re-Stage 4 and done a excellent job!
You've failed to clear Stage 5, but...?
You've cleared Re-Stage 5 and done a excellent job!
You've cleared Stage 6 and done a excellent job!
You've cleared the Love Stage with adult Kuon!
You've cleared the Love Stage with Kuon!
You've cleared Stage 7 and done an excellent job!
And now we returned back to the beginning of the game...
I remembered all what I've experienced with him.
Meet the Great Octopus and fulfill her wish!
You've cleared Stage 2 and done a good job!