Here is the full list of all 15 Minoria achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Abandoned your mission in favor of the witches.
Defeated Harina.
Acquired the Frailty Incense.
Warmed up Almu, the slug girl.
Collected all the archives.
Executed a total of 1000 witches and enemies.
Purified Princess Poeme.
Purified the witch deity Parushee.
Purified the Witch of Lust.
Collected a total of 20 silver coins.
Defeated Frikka, leader of the thieves.
Purified the witch deity Saora.
Purified Sister Devoir.
Rescued Princess Amelia from a group of witches.
Defeated a major enemy without taking a hit.