Here is the full list of all 15 Rosenkreuzstilette achievements.
Defeat the Deviled Egg without taking any damage.
Finish the game as Grolla in 60 minutes or less.
Finish the game as Spiritia in 60 minutes or less.
Complete a stage without taking any damage.
Defeat a boss with only one point of Vitality left.
Max out your reserve of Extra Lives.
Finish the game as Grolla Seyfarth.
Collect all 100 coins in Schwer-Muta's domain.
Run out of time while facing Zorne Zeppelin.
Finish the game as Spiritia Rosenberg.
Defeat Count Zeppelin.
Defeat the 8 numbered members of Rosenkreuzstilette.
Max out your supply of Cross Tanks.
Add the spunky Lilli to your arsenal.
Complete the Prologue stage.