The Ash Demon King and the Seven-Day Academy

Eighteen years have passed since the Demon Lord was defeated. The Seven Luminaries Academy, once a training ground for heroes, has transformed into a bustling academy city where different races study together. But beneath the peace, tensions simmer between humans and demi-humans, large nations and small. Celestia, a princess from the small kingdom of Lumeria, sincerely wishes for a world where everyone can smile. During a soul-quieting ritual held where the Demon Lord fell, she discovers a boy