Koharu Asai, upon discovering her younger brother is being bullied, decides to infiltrate his school disguised as a boy. To stop the bullying, she identifies the ringleader's weakness and successfully forces him to cease his abuse. However, during the process, her biggest secret—her true identity as a woman—is exposed. Resistance proves futile as she is reduced to a male-disguised sex slave, enduring gangbangs, blackmail, and humiliation. The story concludes with a heartbreaking and tragic ending.