Here is the full list of all 10 The Last Saintess achievements.
May the Goddess of Discipline take care of you...
Their will will be remembered forever.
With a new outfit
Come, undead!
For the Goddess of Discipline...!
Feeling a little stronger.
It's an honor to be with you.
She has lost her memory from when she was alive, but her magic remains menacing.
It's not just temples where the undead thrive.
You have stopped the Dark Siren at the Siren's Tomb. She will sleep for a while among the sunken ships.