Kor, a young man living in a small village by the sea, is enhancing his sword fighting skills under the careful supervision of his grandfather. Impressed by Kor's growing skill, his grandfather bequeaths to him an unusual weapon known as a Soma.
Soon afterwards, while watching the house in his grandfather's absence, Kor meets a young woman named Kohaku who has come searching for his grandfather. Kor is enchanted with the young woman, the first girl he's ever met from outside his village.
However, a mysterious witch soon appears who casts a spell on Kohaku's Spiria, the embodiment of her heart and soul. Kor attempts to lift the spell by connecting to her Spiria through a technique known as a Spiria Link, but while doing so he accidentally shatters her Spiria Core, the source of her emotions.
Kor, armed only with the Soma given to him by his grandfather, must now set out on a journey to find a way to make Kohaku's Spiria whole once more.