Here is the full list of all 15 Libra of the Vampire Princess achievements.
Cleared Lycoris route
Selected Lycoris route
Selected Aoi route
Cleared Aoi route
Selected Aoi & Lycoris route
Selected Mari route
Cleared Mari route
Cleared Calen route
Selected Calen route
Shut down game first time
Played game 1 hour
Watched opening movie
Started game first time
Played game 10 hours
Played game 30 hours