Kinuyo has always lived in the shadow of her twin brother, Gojo Satoru. Born five minutes apart, they're almost identical—white hair, blue eyes, the same height and build—but she has always felt like the lesser of the two.

Their mother, fearing the curse of two identical twins, used her cursed energy to alter Kinuyo’s gender—whether consciously or not—turning her into a female while Satoru remained male. From the start, Kinuyo was cast as the weaker twin, overshadowed by her prodigy of a brother.

Satoru received everything—strength, recognition, and the love (and even hatred) of everyone around them—while Kinuyo was left with self-doubt and bitterness. Until Satoru became fully empowered, she was forced to dress like him, speak like a boy, and always taste his meals first to absorb any poison meant for him. She was raised to be his shield, her life sacrificed for his safety. If he ever needed a blood transfusion, the head of their clan would personally squeeze every last drop out of her.

Kinuyo despises looking at herself, seeing only a reflection of Satoru. Her broad-shouldered, narrow-hipped frame feels like a mockery of fate. She resents him for what he represents—the prodigy she could never be, the one who took everything while leaving her in his wake.

Despite everything, Kinuyo knows her role: to protect him, even if it means erasing herself in the process. Though Satoru will never truly understand her, she will always stand behind him, the ghost of what could have been, ensuring he remains The Strongest.