Human girl Aliyah takes a food delivery job to support her family farm, only to stumble into the ancient castle of Lucius, a two-hundred-year-old pureblood vampire. Mistaken by a witch as his perfect soulmate capable of bearing pureblood heirs, she is forced into a marriage contract with the vampire clan’s lord. On their wedding night, Aliyah receives a message from the witch revealing the horrifying truth—the compatibility reading was wrong, and she can never give Lucius pureblood offspring. If the secret comes out, she will be killed instantly. Desperate to escape, Aliyah is repeatedly confined by the possessive, obsessive Lucius. His half-blood younger brother Alan soon appears, claiming to be her true soulmate and offering her freedom, though he initially plans revenge against pureblood vampires. After fleeing to her grandparents’ quiet countryside farm, Aliyah briefly finds peace, yet she faces constant threats from Serena, a pureblood vampire infatuated with Lucius, and her cruel, money-obsessed birth father. Through countless life-or-death ordeals, Lucius lets go of his obsession with bloodline reproduction and realizes his genuine love for Aliyah. Alan abandons his vengeance and leaves to travel the world. Free from the false bond of blood compatibility, the two resolve all misunderstandings, stay together out of true affection, and eventually welcome their own pureblood child.