Here is the full list of all 15 Sakura MMO Extra achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Two girls with too much energy
Everything has to be perfect
A knight at heart - not a maid
Bonnie warmed up to you
Probably not the easiest job change
Meet an old friend
Or a new service
Hugged out of trance
...or a magic spell?
Let Holly and Aislinn help out
Review Eleri's and Fion's maid outfits
New piece in the wardrobe
Is that really it?
You were not the only one thinking about it
Leaving was never an option