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