There was a legend that said when a person didn't have a shadow, they were fake. They weren't real people. They took the appearance of a human, but in reality, they were demons taking the shape of a human.
It was believed that this was the balance between the two species. While demons caused havoc, they also learned cunning tactics to defeat humans. One example was turning themselves into humans. When a demon took human form, they had to sacrifice their shadow to make it possible, which made them easier to detect despite their trickery.
Thus, humans, with their superior mental powers, became stronger than demons in that regard, while demons, with their naturally gifted bodies, were left behind in terms of intelligence but excelled in physical strength. This balance was believed to make the fight fair.
"Which I think is really stupid. There's no fairness in this world," Leonard mumbled weakly as he woke up after three days of unconsciousness.
