Here is the full list of all 12 Sakura Knight achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Accompany Rune
Meet Felicias sadistic side
Accompany Tart
Accompany Felicia
Get a fresh start with Tart
Find the thieve
Meet Rune the wolfgirl
Learn to relax
Cooling of the Elves way
Meet Felicia Maribelle d'Argento
Meet the humble cat witch
Meet your host