No missable achievements (plus 22 unknown)
Sign in with Steam or Xbox to track your progress, and:
Start the game.
Use a phrase for the first time.
Swap to a different person for the first time.
Finish the first meeting of Kokurase.
Make the school statue bald.
Put back all stuff in the broadcasting room.
Finish jointing of "red thread of fate".
Hide Sakura from the view of Yoshimitsu.
Withstand in the locker room without being found.
Fulfill the request in any way.
Finish the game.
Encounter a beginning of love.
Take the request from Kotarou.