Aoi Mizutani, the Blue Cellar Striker, infiltrates Higurashioka Academy disguised as a new transfer student. In reality, she is an undercover investigator sent by the Ministry of Education, secretly gathering evidence of the school's corruption while posing as a male student. No one knows her true identity—until a classmate suddenly vanishes, abducted for human experimentation. Aoi transforms into the Blue Cellar Striker and confronts the evil school principal, but when the student council president is taken hostage, she is forced to surrender. The principal, determined to uncover her true identity, subjects her to relentless humiliation and complete subjugation… [BAD END]