Copywriting
She is not a real human, but blends into the human world for her mother's wishes;
He is an ordinary boy (yes, a boy) who was lucky enough to be picked up and brought home by his adoptive father.
One day his adoptive father said to him, "Xiao Huihui, I found your sister."
Soon after, he discovered to his horror that this sister seemed to be no ordinary person...
The story is about siblings, the female protagonist has superpowers and the male protagonist is a weakling.