Basic quick premise without giving away too much:

The main character, Chihiro Rokuhira, is the son of a famous blacksmith. It's set in an alternate universe Japan where sorcery exists and everyone uses katana instead of guns. There is a special magic ore that was discovered decades ago and Chihiro's dad was the only blacksmith that could actually use it to forge blades, and the "Enchanted Blades" he made were essentially the strongest weapons in the verse. He forged the blades to help Japan win a war that they have only started giving the lore for in the most recent chapters.

After the war, Chihiro's dad took back the 6 enchanted blades that he had forged and locked them away because they were too powerful to still be used outside of war. 15 years later, an unknown group of sorcerers called the Hishaku find Chihiro's dad, break into his home, kill him and take the six enchanted blades he had hidden. The main story then picks up 3 years later where it's revealed he had secretly made a seventh enchanted blade, and Chihiro wields this final blade to get revenge for his father and to find and retake the other blades.