A sudden email arrives to trainer Hayami. The sender is a masochistic woman named Ruka, who confesses her desire to submit completely. Hayami immediately heads to Ruka's home to hear her plea in person. Ruka's extreme desire for submission gradually becomes clear. Each time she obeys a command, she expresses joy and appears deeply satisfied. Pain, humiliation, and even sex with an unknown man are all part of her happiness. Her demeanor reveals an intense passion for absolute obedience.