[Contest] Owner of the Black Wings

Three thousand years ago, the fall of an archangel turned Heaven upside down. With the suddenly diminished command hierarchy, Heaven slowly crumbled, and now lies in utter ruin. Thirteen years ago, an oracle prophesied that a child would come to save Heaven. All the angels devoted themselves to finding this child, but the search was foiled by a fallen angel who appeared out of nowhere. Why does the fallen angel seek the oracle's child? And what does he intend to do with the child?