When the aristocratic boys reach eighteen, they lead a number of beautiful girls to establish a knighthood, a world similar to a game in which they are obliged to face the threat of the nation. The eldest son of the ordinary Baron, Ast, also summoned a candidate girl to establish the Knights. However, he was able to summon only the lowest rare character, who is said to have the lowest qualities … While receiving ridicule and contempt from other aristocrats, Ast, who remembers spending time as a Japanese in his previous life, determined to rise up with Low-Rare Characters.