A brief description of the manga Useless Wizard:
In Fortelnia, a world where strength and destiny are all determined by the rank of “existence power” a power that people born with. Aruto, who has only the lowest rank of existence [☆1], is so powerless that his girlfriend Hanna is killed by Gamizin, the world’s most powerful mage. However, Aruto, who has lived with regret in his heart, gets a chance to start his life over after death–? Making full use of his “crafting skills,” a special power given to him by God, he sets out on his second life to save Hannah’s life!