A rural gynecologist named Gorou Amamiya has his life forever changed by a young, terminally ill patient, Sarina Tendouji, who instills in him a deep fandom for the rising idol Ai Hoshino. Years later, Gorou is shocked when a pregnant Ai secretly arrives at his hospital to give birth, away from the public eye. Before he can help deliver her children, Gorou is murdered by a deranged stalker of Ai. In his final moments, he hears the cry of a newborn. He awakens to find he has been reincarnated as Aquamarine Hoshino, one of Ai's twin sons, retaining all memories of his past life. He soon discovers that his twin sister, Ruby, is the reincarnation of his former patient, Sarina, who now has a second chance to live out her dreams.

The twins are raised in secret by Ai, who continues her meteoric rise as the center of the idol group B Komachi. However, their happiness is shattered when the same obsessed fan who killed Gorou finds their home and fatally stabs Ai. In her dying moments, Ai expresses her love for her children, a moment that becomes the driving force of their lives. As the twins are adopted by the president of their mother's agency, Strawberry Productions, Aqua, having witnessed the murder, deduces that the stalker was manipulated by an accomplice. Convinced that his biological father, a figure still active in the entertainment industry, is the mastermind behind Ai's death, Aqua vows to enter show business and exact revenge. Ruby, meanwhile, sets her sights on following in her mother's footsteps to become an idol.

As teenagers, Aqua and Ruby enter the entertainment world through different paths. Ruby works to revive B Komachi, recruiting the sharp-tongued former child acting prodigy Kana Arima and the popular YouTuber Mem-cho to form a new version of the group. Aqua, operating under a calm and calculating exterior, takes on acting roles to gain information. He lands a spot on a reality dating show, LoveforReal, where he witnesses the brutal reality of social media toxicity firsthand when a contestant, the diligent young actress Akane Kurokawa, becomes the target of online hatred. To save her reputation and further his own goals, Aqua publicly creates a fake relationship with her, turning them into a popular "business couple".

The investigation intensifies during the production of a stage play adaptation of the manga Tokyo Blade. Aqua, Kana, and Akane are all cast, leading to intense rehearsals where acting styles and personal rivalries clash. Here, Aqua meets the lead actor, Taiki Himekawa, who is later revealed to be his half-brother, narrowing the search for their shared father. Aqua’s focus on revenge deepens, leading him to temporarily distance himself from his loved ones to protect them.

In a later arc, Ruby takes a more active role in the investigation, hosting a variety show to build connections and uncover secrets. She learns that their father, Hikaru Kamiki, is not only alive but is a charismatic and deeply disturbed individual who has continued to manipulate events from the shadows. When Kana gets caught in a potential career-ending scandal, Aqua orchestrates a public diversion by revealing the explosive truth: he and Ruby are the secret, illegitimate children of Ai Hoshino. To deliver the final blow, Aqua directs a biographical film about his mother titled The 15-Year Lie, designed to expose Kamiki's crimes and draw him out. The plan culminates in a final confrontation that forces Aqua to decide how far he is willing to go for revenge, leading to a devastating and controversial conclusion that leaves Ruby to carry on their mother's legacy.