Ikki Kurogane is a Blazer, a person who can materialize his soul as a weapon. Unlike most Blazers, however, his aptitude for magic is virtually nonexistent. Branded a talentless failure and nicknamed "Worst One," he has spent his life honing his swordplay in order to become a Mage-Knight nonetheless.

Stella Vermillion is the second imperial princess of the Vermillion Empire and a powerful Rank A Blazer. Having spent her whole life undefeated in battle as a result of her incredible natural talent, she travels to Japan in search of powerful opponents, hoping to grow ever stronger and become an accomplished Mage-Knight herself.

The two meet at Hagun Academy, one of seven Mage-Knight schools in Japan, and soon realize that they share the same goal: to become a powerful Mage-Knight renowned for their hard work and skill, regardless of their level of talent. In order to reach that goal, their first step is to meet in the finals of the Seven Stars Battle Festival, a no-holds-barred tournament that gathers the strongest student knights from all seven schools across Japan, and fight for the title of Seven Stars King.

Can Ikki and Stella fight toe-to-toe with even the strongest of Blazers and achieve their dream of reaching the peak of knighthood?