Due to the stress from work and her introverted personality, Sai developed a perverse fetish. During her leisure time on a footpath, she was caught by a stranger while indulging in public masturbation. Her overly obscene exposed state was seen by another person, causing her legs to tremble and her body to shake, but she couldn't resist the man's lecherous gaze, becoming wet between her legs, and ultimately volunteering for humiliation training. Wandering naked, outdoor restraints with pleasure torture, and the man's extreme exposure orders stirred her sense of shame into wanting him to "see more of this filthy me"
