Yuusha Ninteikan to Dorei Shoujo no Kimyou na Jikenbo

A past threat nearly wiped out humanity when the "Demon Lord" emerged, but the "Heroes" defeated it and saved the world. To prepare for a potential return, a system was established to maintain a constant presence of heroic individuals. Centuries later, in a time when the Demon Lord is remembered only as a legend, Miguel, a government official responsible for verifying heroes, and his companion, Dia, search the land for potential candidates. Miguel learns of a "holy hero," believed to be the reincarnation of the legendary hero who once defeated the Demon Lord. Upon visiting the mining city of Felicidad to look into the claim, he witnesses a girl performing miracles, known as the "Holy Hero." This marks the beginning of a mystery involving these miracles and the possible return of heroes.