Saki Mizumi's son causes a serious injury to a friend, forcing her to start covering up the incident. However, when the truth leaks to the homeroom teacher and the grade supervisor, she is coerced into enduring disturbing anal training to ensure her son can remain at school. Driven by maternal love and compassion, Saki is pushed to her limits in this absurd situation, ultimately being subjected to aphrodisiacs. The story portrays Saki's determination to face any hardship for the sake of her child.