Here is the full list of all 14 Crimson Spires achievements.
Complete all four romance paths with a good ending
Get the good ending on the Liam path
Get the bad ending on the Liam path
Fully embrace the ways of the Batailles
Get the good ending on the Julian path
Complete Julian's path without losing your humanity
Get the bad ending on the Julian path
Get the good ending on the August path
Get the bad ending on the August path
Get the good ending on the Maddy path
Get the bad ending on the Maddy path
Choose a partner for the second half of the game
Witness Julian's true nature