Rio Ogawa, a female teacher at a school run by her father, the principal, finds her life shattered when her father is falsely accused of assaulting a sex worker and arrested during a campaign to shut down a local brothel. Desperate to clear his name, Rio visits the victim but instead falls into an unexpected trap, forcing her into a life as a soapland prostitute. Despite her pure heart shaped by years in the academic world, she is compelled to walk this new path against her will. The story delves into her inner turmoil, emotional struggles, and fragile hopes for the future, as she becomes entangled in two opposing worlds—the disciplined environment of school and the brutal underground of the sex industry—leading to a life-altering descent into slavery, humiliation, and complete submission.