At Koryo Academy, students battle with weapons forged from their souls. Kokonoe Tor, however, is an Irregular. He doesn't have a weapon--he has a shield! To gain the strength he seeks--and thus unravel the truth of his tragic past--he must form a Duo with another student. But first, he has to figure out how to share a room with a girl, the graceful fighter Julie Sigtuna, and not die of total awkwardness.