Well, i must say, i watched this Anime, because it was available on Amazon Prime for limited time only, i was nicely surprised, despite just the average score. I was entertained for the last 2 days watching it. The Story is light, yet for Anime with just 12 episodes it was interesting and complete, no plot holes or any uncertainties. I would say it was done just right, really. And the Ecchi Harem moments were pretty entertaining, it had also it serious moments, cause of the supernatural, scifi and military theme. This formula for a successful Anime works quite often. Art is good, the typical Anime design,about the sound i have nothing to comment, i usually skipped the OP after first episode, it does not have any remarkable OSTs
Since the Anime is on the lighter side, not to deep. The characters were exactly so, light, with a backstory which had the perfect level seriousness for a short Anime, and in 12 episodes all characters had their moment of development where they could shine.
Overall i do recommend this Anime, trust me for the couple of evenings at home, perfect light Entertainment.