Najica Hiiragi is a perfumer and an undercover agent whose responsibility is to capture rogue humaritts – androids engineered for combat. In her pursuit of this goal, she collaborates with Lila, a humaritt whom she mentors in the art of espionage. The more Najica and Lila work together, the more they learn about the humaritts' mysterious background and their exceptional capabilities, each new mission unveiling new revelations.