Maryoku 0 de Tsuihousaremashita ga, Daiseirei to Keiyakushi Maken no Chikara ga Kakuseishimashita

Elias, an orphan, receives a demonic sword from the master who raised him. He joins a hero party on their adventures, but he cannot unlock the sword's power and is eventually cast out as useless. Venturing alone as an adventurer, Elias encounters Emma, an elf girl pursued by a dragon. Together, they confront the dragon, receiving unexpected help from a benevolent spirit named Undine. With their combined efforts, they manage to defeat the dragon. Elias, Emma, and Undine then embark on a journey to the elf kingdom together.