18+ Yuusha Densetsu no Uragawa de Ore wa Eiyuu Densetsu wo Tsukurimasu: Oudougoroshi no Eiyuutan

Yukina was a young man who hailed from the same village as the Hero who shouldered the fate of the world. Through a certain incident, he got ahold of the talking spear, Gram. It was a weapon that was on par with the legendary sword the Hero wielded.

(Source: Futabasha, translated)