The "no Ko" suffix often leads to confusion with this major hit. Relationship Dynamic:

Love is frequently used as a catalyst for a character's "awakening."

As Sarina, Ruby was a terminally ill child who fell in love with her doctor, Gorou Amamiya. She died dreaming of marrying him. Reborn as Ai’s daughter, she discovers that her beloved doctor (now Aqua) is her twin brother.

To understand any romantic storyline in Oshi no Ko , one must start with Ai. She is the gravitational center around which all emotional trauma orbits. Ai’s relationship with Hikaru Kamiki, the father of her twins, is the primal sin of the narrative. It was not a romance; it was a disaster. A teenage idol falling for a younger, charming actor, resulting in pregnancy and, ultimately, her murder.