Eighteen year old Manami Katagiri has faced numerous hardships thanks to his father's criminal behaviour and mother's death: he had to drop out after middle school and begin working in a factory to take care of his little sister. For various reasons he decides to re-enroll himself in high school and better his life. However, at the entrance ceremony, he encounters a "princess" whom he thinks has had everything given to her on a silver platter, not that her thoughts are any better. What will become of their time in high school?

Zan Ruu lives a carefree lifestyle with his military father and brother. However, one day a mysterious airship attacks the capital, and danger approaches Princess Emma. Zan hurries to rescue Princess Emma, but who appears before him...!?