The Past Always Comes Back

Habaek, the god of water, must find the three sacred stones in order to return and become the King of The Divine Realm; he seeks help from a divine servant, So-a.
So-a teaches the "water demon" how to co-exist in the human world, but on the way he encounters a dear friend of So-a's that makes him believe they'd met before. He along with everyone else had found out that not only does that girl look fimiliar but also that she had been helping So-a survive the Gods and/or higher beings.
Habaek among his other desciples from the Divine World are convinced the girl is not from this mortal world but the one they had originated from.
"There are some things that are better left forgotten," her peircing grey orbs stare deep within my soul.