A girl named Riko carelessly skipped reading the pre-consent explanation for a clinical trial. Her ignorance and vulnerable mind became the gateway to tragedy. As she struggles to endure treatment as a test subject, days filled with humiliation and disgrace continue relentlessly, gradually breaking her spirit. "Cooperation in the Clinical Trial of Laxative Shin●," portrays a harrowing narrative where profound psychological depth intersects with cruel reality. The protagonist's mental anguish and distorted human relationships are depicted with striking realism, delivering a powerful impact to readers. As the story progresses, Riko's inner transformation is clearly conveyed, making her suffering deeply palpable.