Riho Asao was leading the investigation to dismantle the vicious drug trafficking organization "Kuro Ran-kai." One day, she heads to a dilapidated building where a tip-off was received. However, it was a trap set by Kuro Ran-kai, who had planned to capture Riho from the beginning. She pretends to be strong in front of the criminals, desperately trying to appear fearless, but she is steeped in pleasure and loses her reason. And the "sex beast" hidden within her awakens.