In "Oshi No Ko," Vol. 13, the story of Ruby continues as she finds herself in the midst of filming "The Fifteen Year Lie." In this film, she plays the role of her own mother, Ai, which presents a unique challenge. Ruby must not only shine as an idol and television talent but also prove herself as an actress. This complex situation leads to a deep exploration of her relationship with her mother, both in her current life and in the past. The narrative highlights the challenges and emotions associated with the pursuit of success in the entertainment industry and offers insight into the dynamics between mother and daughter. The blend of humor and serious themes makes this work a captivating reading experience.