Here is the full list of all 22 Muv-Luv photonflowers achievements.
Watched all Theater movies
Viewed Schwarzesmarken PV
Completed Inheritance
Completed all sidestories!
Completed Chicken Divers
Completed Confessions
Completed Rain Dancers
Completed Atonement
Checked out an Alternative sidestory
Scrolled through the Alternative Timeline
Completed Learning to Lead
Completed Learning to Love
Completed The Yakisoba Festival
Completed Never Judge a Book
Completed The Case of the Missing Tail
Completed Best Friends Forever!
Completed Before the Cherry Blossoms Bloom
Opened the Load Menu
Opened the Save Menu
Checked out an Extra sidestory
Checked out Gallery mode
Opened the Options Menu