William, an ancient vampire sovereign burdened by blood‑curse and long‑term imprisonment trauma, originally intends to form a blood contract with pure‑blood human Henry to stabilize his royal power. However, he gradually gets healed by Henry’s pure‑hearted toughness. Once a promising underground‑fight star, Henry ends his toxic relationship with the scheming vampire Carlos after uncovering he is merely treated as a plaything. By chance, Henry meets William and gets force‑marked by him, drawing himself into age‑old vampire faction conflicts. Consumed by envy for William’s power and Henry’s unique pure‑blood constitution, Carlos conspires with ambitious noblewoman Alice and conservative elder Charles. They repeatedly set traps, spread slander, and try to drive a wedge between the two protagonists. Henry awakens his latent pure‑blood human power and learns of William’s miserable millennium‑long imprisonment experience. He chooses to stand firmly by William’s side. The pair defy ancient vampire taboos and forge an eternal life‑and‑death bond. Carlos resorts to forbidden sorcery to seize control of Henry’s mind, forcing William to shatter the malicious blood contract and crush his plot. Refusing to accept defeat, Charles activates the ultimate vampire ritual, the Blood‑Abyss Sacrifice, in an attempt to undo their bond and seize supremacy. Combining William’s progenitor vampire power and Henry’s pure‑blood humanity, the two break the forbidden spell and put down the rebellion. All antagonists meet their doom, and the old, corrupt vampire codes are abolished at last. Having shaken off the curse’s shackles, William and Henry end centuries‑long strife, ushering in a peaceful new era for vampires and staying together for the rest of their lives.