Things aren't what they always seem, neither is Dusk Lunar.

Dusk is a hybrid, one of angelic demon blood. His father the current  ruler of Paradise and his mother of the Void, Dusk being heir to both thrones.

Although born in the heavens, he is forced to reside in darkness. It wasn't until his demonic features started to show, did he learn the cold truth to his father's plans for him and what really happened to his mother. 

Dusk is casted away to live his remaining days on Earth, a punishment for storming the gates of Paradise in a fit of rage. As he falls, he vows to over-throw his father and take his place as the rightful king of the realm.
 
Upon literally crash landing into a home when falling, he meets a human girl-- The very one who will have him reflect on his life onward.

Yet, little does he know, she is the actual key to unlocking the gates to Paradise.