Erina is about to be an exchange student to her fiancé's prestigious boys school for one month.
However, Erina's fiancé has also decided to be an exchange student to her own school.

While being filled with anxiety, she is protected by her fiancé's older brother, the student council president.
Or so she believes...

In school, she is assigned to the "Sex Slave Committee". Students, teachers, headmaster, janitors... Anyone can violate Erina, break her heart or turn her into a sex toilet.