For orphan-turned-prosecutor Hyeon Jeongui, ambition is the only thing that matters. When a minor slip demotes him to a backwater outpost, his climb up the legal ladder seems finished, until a devil named Seo Cheong offers him a shortcut to the presidency. The price? Giving himself up to the insatiable demon every single night. The dark bargain works all too well, propelling Jeongui to chief prosecutor in record time. Deciding he has milked the arrangement for all it is worth, Jeongui sets his sights on becoming a chaebol son-in-law and tossing the demon aside. But Cheong has no intention of letting his plaything go, and breaking an infernal deal comes with a brutal reckoning.