Tsuma Netori Kan: Bijutsu Kyoushi no Baai, Episode 1 Raw

妻ネトリ 姦 美術教師の場合 / Tsuma Netori Kan: Bijutsu Kyoushi no Baai

A story about when Makoto was a trainee at the school.
Yurina Suzukaze, a popular teacher who teaches drawing to her students in the art room, is married, and her husband works alone in Italy. When her father, the owner of her gallery building, falls ill, she becomes a temporary teacher at the school until her condition improves.
Sakakura, her senior from college, who introduced her school to Yurina, has an unusual liking for her, and together with Yasuno, who sympathizes with each other, a plan to train Yurina is put into motion.
Following orders from her director, Yurina will participate in an exchange training session. On the day of her departure for the exchange training session, she drinks the tea that Sakakura recommended to her, and then her feet become unsteady, her eyes darken, and she collapses.
When her girlfriend Yurina wakes up, she trembles at her situation. She was strapped to her training chair completely naked, with a gag ball in her mouth and a potion applied to her nipples and clitoris, making her erect.
Sakakura starts talking about giving her a boost to Yurina, who is about to lose her mind. She is told that for half a month from today, she will be confined in this training room and live her training life.
For what seemed like an eternity, Yurina was subjected to horrific training.