After starting to live separately from her husband due to his single-person assignment, Yoko began to worry about her only son Ken's behavior. Ken, who was dissatisfied with everything and quick-tempered, became disliked by his classmates and eventually instigated a 'rebellion.' Shocked by the betrayal of his trusted friends, Ken transferred schools to his father's single-person assignment location. However, the tragedy did not end there. When Yoko was alone at home, the doorbell rang…
