Ivy, a human girl suffering from a terminal illness, accidentally stumbles into a vampire castle and is forcibly bound by a contract to Julian, a pureblood vampire lord. To avoid being forcibly marked by the female elder Ella, Julian enters into a contract marriage with Ivy. As they spend time together, Julian discovers that Ivy is hiding a huge secret related to his mother's death, and the mysterious power sleeping within Ivy gradually awakens. Through being hunted, facing conspiracies, and uncovering hidden truths, the two go from a contract master and servant to true loves, ultimately revealing the truth behind Julian's mother's death.
