I Became the Villain Boss in a Female-Lead Romance Novel

Betrayed by her best friend and poisoned by the Regent she married, she dies branded a traitor—only to wake up at sixteen with a second chance at revenge. But there's a twist: a mysterious System forces her into the role of the cold, calculating Regent himself. She can't expose her transmigration or kill the heroine too soon. Now trapped in the body of her greatest enemy, she must navigate palace intrigue, forbidden romance, and a storyline that wants her dead. Can she rewrite fate before the novel's tragic ending catches up?