Here is the full list of all 15 Muv-Luv achievements.
Saw Miki ending in EXTRA
Unlocked Jukebox mode
Saw one possible ending of Unlimited
Saw Kei ending in EXTRA
Saw Common End 2 ending in EXTRA
Saw Sumika ending in EXTRA
Started Unlimited
Took five Drill Milky Punches to the face
Saw Common End 1 ending in EXTRA
Saw Meiya ending in EXTRA
Started Muv-Luv!
Saw Chizuru ending in EXTRA
Saw all possible endings of EXTRA
Saw all possible endings of UNLIMITED
Completed the CG Gallery