The group, known as the "Ring Enthusiasts Club," abducts the woman they've targeted and recruits members on a dark website frequented by ring enthusiasts, offering the experience for a fee. This time, their target is a 19-year-old college student, Miyama Mika, who has just moved to Tokyo to live alone. The vulnerable girl, who carelessly shares her personal information on social media, became the perfect prey for the men.