Here is the full list of all 15 Sakura MMO 2 achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Reach Fion's ending.
Reach Neve's ending.
Reach Eleri's ending.
Meet Gardenia - the omniscient entity.
Fion gets caught... again.
Help with the housework.
Get to know what happened to the necklace.
Find yourself in an unknown room.
A loyal knight keeps their word.
The meeting of the princess and the guild master.
Safe Aislinn from falling.
Relax after a long day of research.
Fion isn't interested in discussions.
Witness Maidie getting... attacked.
Take a nice bath with Eleri.