Katsuragi Ria

Ria is Masato's younger sister and a childhood friend of Hisui, her "Hime-oneechan". She left the city with her brother and parents a few years ago but has recently returned to join the high school run by Sleipnir, a military branch specializing in AD technologies.

Since her integration in first year, Ria quickly became one of the best students, her AD armor being very famous for its impenetrable defense.