Kami no Hikari ~~ The Legend of God's Light

Prism Giou... A girl who knows nothing about her parents or her past except for memories of a strange boy with haunting silver eyes. He leaves her on her 12th birthday and comes back on her 13th birthday. It's supposed to be a dream come-true, the reunion she's waited for... But something unexpected happens and her fate changes into something she's never imagined before...

(Uragiri Wa Boku No Namae Wo Shitteiru FANFIC)