After receiving some injuries following a fight with some punks, orphan Fuuka Reventon is helped out by Einhart, who invites her to come to the Nakajima Gym afterwards. Noticing Fuuka's potential as a martial artist, Einhart offers her a part-time job at the gym. Despite having a hatred of martial arts after losing to her former friend, Rinne Berlinetta, Fuuka accepts the job and starts off as a sparring partner for Vivio and her friends, becoming surprised by how strong they are. Hearing that Vivio is the one who broke Rinne's winning streak, Fuuka faces her in another sparring match, deciding to stop running away and aim to become stronger.
Fuka Reventon et Rinne Berlinetta, amies d'enfance ayant grandi ensemble dans un orphelinat, se sont séparées après une dispute qui les a éloignées. Désormais sans abri, Fuka survit en participant à des combats de rue. Un jour, elle est secourue par Einhart Stratos, une combattante expérimentée, qui reconnaît son potentiel et lui propose de rejoindre le gymnase Nakajima pour s'entraîner aux arts martiaux magiques.
Fuuka e Rinne vivono in un orfanotrofio e sono legate da un amore quasi fraterno, mentre affrontano le avversità della vita e sognano un futuro migliore. Purtroppo, una seconda separazione sta per cambiare il destino di entrambe.