This is an episode centered on Sato and his time in the army. An origin to his love for carnage and slaughter is shown in this episode and it makes you sorry that series weren't that much centered on action. The quality of the story is better in this episode than in the whole series in my opinion. Sato is a monster, yeah, but he is a fascinating monster. And after watching this epiode, I understood that I wouldn't mind having the whole series from Sato's POV rather than from Nagai's which is a very bad main character in my opinion, because it takes toolong for him to form his own character and by the time he does, two seasons of the series have passed. Maybe he improves in unavoidable third season, when it comes sometimes in the future. Anyway, I give this episode a 8/10! It's a good OVA and a must watch for the fans of the series!