Formly known as Gozen, the head of Easter. As Gozen he promised the company employees a successful career if they can present him the Embryo. According to the manga, he wishes for a rare one-of-a-kind jewel, thus Easter's search for the Embryo.
Hikaru, is unique, he did not have a Heart's Egg in him like almost all children. In chapter 41, after his past is revealed, he finally gains one. It turn out that his egg was actually the shining white egg the others previously suspected as the embryo.
Hikaru is Kazuomi Hoshina's grandson.