This series began as a self-published dojin, but slowly made it as a still picture drama, and eventually the Japanese division of the French company Ankama Games decided to produce it as an anime.
I'm getting a lot of hype for this project, inspired in World War II, but with mechas and drama between girls with supernatural powers. Talk about an explosive combination!
The new streaming trailer can be seen here. in their official site.
But here's a youtube version thanks to HazuStark: