BNA unfolds in a world where humans and Beastmen have been at odds for ages. Beastmen are a species capable of changing shape thanks to their genetic “Beast Factor,” and that conflict has driven many of them into hiding. Anima City was built as a refuge where Beastmen could finally live free from human interference, but the city’s promise of safety is far more fragile than it first appears.
When Michiru Kagemori, a human who suddenly turns into a tanuki, arrives during the town’s 10th anniversary festival, she learns that Anima City is a long way from paradise. After witnessing an explosion in the square, she is confronted by Shirou Ogami, a seemingly indestructible wolf and the sworn protector of all Beastmen. As the two pursue the criminals behind the bombing, they begin uncovering that Michiru is anything but an ordinary Beastman. Her mysterious past and uncanny abilities put her at the center of a wider conflict, and the question becomes whether she could be the missing link between humans and Beastmen.