Sabitsuita Ken" wo Tameshi ni Kyoukashite Mitara, Tondemonai Maken ni Bakemashita

In this world, upon turning twelve, individuals are bestowed a special armament known as a sacred weapon by the gods. Rust, a young boy residing in a remote village, shares a dream of becoming an adventurer alongside his childhood friend, Ruby. While Ruby is granted the highest rank, A, Rust receives only a battered, F-ranked rusty sword. Unlike his childhood friend, who is recruited by an elite party, Rust is told that his dream of becoming an adventurer is utterly unattainable. Refusing to give up, he chooses to press forward and fight using his humble weapon. By steadily defeating weak monsters little by little, he gradually strengthens the blade. After three years of perseverance, the rusty sword finally reaches weapon level 10. At that milestone, a hidden skill awakens within the weapon, causing it to evolve into an overpowered magical blade. This marks the beginning of an epic journey for a boy who was always dismissed as the weakest.