In a world full of destruction...humans has to live a life of fear...as war from different country arises the demon lords see these as an opportunity to dominate earth and these made life harder for humans as demons began to take full charge on earth....demons began to mix with humans...and most of them began to take women as wives which made earth new population...a way different evolution of half demon children....And this were Smith came in his mother was human while his dad was a demon lord but was later killed by other demon lords who were in a quest for power...all smith wanted was revenge...but his quest for revenge was later over ride by another....