First of all, anyone who watches this can easily see why parents were advised to remove their children from the theater before it was presented.
The animation is -- STUNNINGLY Beautiful! I can see why another reviewer mistook the story as an tiny war, but I felt it was depicting Athens/Sparta.
The story is pointlessly grim and violent. As an aside, I doubt any man would find it comfortable to fight without at least underwear, if not shorts on. The dangling genitalia was unnecessary to the story, I cannot see one reason it was done.
What is it supposed to be? Is it supposed to speak to the violence and loss of war? Is that something our world doesn't understand, hence a need to waste the (considerable) effort of the artist on? No.
The entire time I was watching it I was frustrated by the wasted talent. He should find a new writer give him a story worthy of his work.