Grace and Shadow — Viola Grace

On a world where everyone has a superpower and the powerless die before puberty, Imgrace is not in for a long and lustrous future. She learns at nine that she will never have a talent, and when her family pretends she never was, her life becomes a routine monitored by bots.
Being asked to help the Guardians in an experiment is one thing, finding out that she has something to offer her people is another. Imgrace is shocked.

Shadow was indifferent to the young woman who had lived her life powerless, until she kissed him. One moment turned his focus from his people to this young, frail woman who had been rejected by every means. He was about to pursue her when his commander shipped her to the Citadel, and then, he had to wait.

Training at the Citadel is surreal, and finding out that she isn't what she thought shocks her to her core but fills her with purpose. She left a void, but she is returning a Guardian.