In this world of humans and monsters, the Sword God has imparted his power unto humans to defend themselves. To the sword dancers, he gave a part of his spirit essence, and to the sheath maidens, he bestowed a part of his divine power. For generations, they have combined their powers to fight the monsters of the land, revered by the people.

Saki comes from a long line of sheath maidens. Although she's the eldest daughter, she doesn't possess any sheath maiden powers. Compared to her younger sister, who showed talent from a young age, Saki is looked down upon by everyone. Yet, she endures with a smile, holding fast to the words of her grandmother, the only person who ever showed her kindness.

Set up by her sister, Saki is blamed when monsters attack the village. Amid the chaos, just as she's about to meet her fate, Saki is saved by none other than Suguru, known as the strongest sword dancer. The wheels of fate begin to turn with this fateful encounter!