On every night that the full moon rises, once his majesty king of Joseon sleeping schedule have been decided, then he'll appear ,the man who covets the kings women making sure there is pain ,when they die ,he drinks their blood,He's name is GWI a vampire.
Every king of Joseon serves and obeys him as he helped in the defeat of their enemy and stabilized their position hence,a promise to always serve him was made. This story has been passed down from generation to generation among the royal court ladies in the royal palace .
One night,on the day the full moon rises, GWI appeared in the royal palace as he often does, he entered the king royal concubine chamber, harrased and then killed her,during the whole process the king was outside the royal concubine chamber shivering while also helpless of the situation .After GWI killed the royal concubine,he drank her blood then left leaving the corpse of the royal concubine for the king to take care of.
Meanwhile,while all this was happening,the crown Prince Lee won was outside the royal palace in his alter ego which is a novel write names Lustful People.He was with his childhood friend Seo Yul at his library where he does his novel writing and also enjoys a free air away from the royal palace. The royal guard were deployed to look for Crown Prince Lee won to be notified of what just happened and of his presence which was needed in the royal palace.