Eren Arkes, who works at the Tamer Guild, was subjected to unreasonable persecution by his co-workers because he had the same black hair as the Demon King, who was once an enemy of humans.

Furthermore, Eren is about to be used as bait to lure wild monsters by the guild master, but he manages to escape and meets an injured Silver Wolf, making use of his ability to talk to monsters and enjoys a momentary peace with his fellow group members.

However, when the humans of the guild burn down the Silver Wolf Forest, Eren decides to become hostile to the humans.

And in order to protect her precious friends, she awakens to her hidden power as a demon king!