In order to save her younger brother, who attends an all-boys school, from being bullied, her older sister, Mahiro, disguises herself as a man and sneaks into the school, grasping the weaknesses of the bullies and was able to stop the bullying. However, Mahiro is assaulted and humiliated by the bullies who find out that Mahiro is her woman. At first she was a bullish Mahiro, but she gradually fell into the pleasure of her masochism, drowning in lust and being disturbed...
