Across Japan, mysterious gates to another dimension known as the “Mato” begin to appear. Within them lies a miraculous resource called “Peaches,” which grant unique abilities — but only to women. However, the Mato is also home to fearsome creatures called “Yomotsu Shuuki,” whose rampages have caused countless disasters. To counter this threat, the government establishes the Anti-Demon Corps, an elite organization of women empowered by the Peaches. One day, Yuuki Wakura, an ordinary high school student, accidentally wanders into a Mato entrance on his way home. Just as danger closes in, he is saved by Kyouka Uzen, the commanding officer of the Seventh Unit of the Anti-Demon Corps. Sensing his hidden potential — and realizing she needs him to unlock her Peach’s full power — Kyouka demands that Yuuki become her “slave.” Surprisingly, Yuuki may find that this peculiar arrangement is far more enjoyable than he ever imagined…