Sumerami Riko

Sixteen years old, a first-year at the same school as Mina.

She has no parents and lives alone—save for one butler—in the largest, most historic mansion in the city.

Riko is a quiet girl, reclusive and disinterested in the world around her.
She expends no effort to make friends at school, and she actively avoids interacting with the other students.

A family secret seems to be at the heart of her antisocial tendencies, however.