conditioning is basically brainwashing so that the girls follow the orders of their handlers, can do their jobs, and so on. the conditioning usually causes them to forget their past as well however that is just a side affect.
The whole mood of the anime is dark, very well done. The little happiness the characters get really hits you, makes you think about the whole concept of being alive.
I often judge animes on their openings. And this one peaked my interest. Because the music is soft and soothing, and you have young girls shooting P-90s. Other than that, amazing song and amazing show
This is a wonderful video..but the only thing that really bugs me is the fonts they use to name the girls! :( But hey...besides that..great anime series!!