A certain country in the demon world. The Demon King was defeated by the hands of one of the heroes, and a competition was held for the title of the New Demon King. The Imperial Four Heavenly Kings Vermilio, who is in charge of the tournament, is furious at the participation of the human hero Helck, who is supposed to be her enemy. After receiving news of the fall of the castle of Urum before the final, Vermilio sets out to retake Urum Castle with Helck and other finalists. With a smile, Helck says, "Let's destroy humans." Are those words true? The truth behind the smile is...

Notes:
・The first and second episode premiered at Anime Expo 2023 on July 1. (Source: HIDIVE)