A new drama starring Ruri Ena and Yuno Mitsui has begun! Ruri's older sister Yuuno happens to be assigned as a student teacher at the school she attends, and her appearance makes her instantly popular at school. This causes a strain on the relationship between the sisters, who were once close, but in fact, both sisters are so careless that they'll do it right away if asked. Isn't it a bit much for the older sister to have sex in the classroom while the younger sister has sex in the nurse's office next door? A truly lewd school paradise!