Bookstore owner Isabella Thorne falls into self-doubt after her ex-boyfriend labels her as "boring." On impulse, she enters the mysterious bar "Nightshade" where she encounters mafia godfather Alessandro Vitale. She "purchases" him for one night with all her savings, unaware that she's provoking the king of the city's underworld. From their initial BDSM games to bloody family warfare, Isabella transforms from an ordinary bookstore owner into a queen capable of fighting alongside him. Amidst the intertwining of power, desire, and true love, the couple endures numerous trials including betrayal, kidnapping, and revenge, ultimately finding their own light within a dark kingdom.