Zoku Tsuma Netori: Ikumi to Shizuka

Ikumi Sunohara, a teacher and wife, grows increasingly accustomed to her existence as a sexual captive. Her actions, including numerous degrading acts, are compelled by blackmail aimed at shielding her sister. However, her sister Shizuka begins to harbor doubts and investigates, ultimately placing herself directly into the hands of the same men exploiting Ikumi.