Here is the full list of all 15 Sakura Magical Girls achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Make every available choice in the game.
There seems to be more trouble on the horizon.
Unlock all of the CG scenes in the game.
Defeat an ancient evil.
Unlock all of Yuki's CG scenes.
Unlock all of Hikari's CG scenes.
Put an end to a forest sprite's pranks.
Witness the full power of the love laser.
Learn of Ayame’s past.
See Yuki while she’s doing promotion work.
Use negative karma.
Enjoy a peaceful cruise with the girls.
Acquire your own wand.
Unlock all of Ayame's CG scenes.
Finally reach the end of your first day.