A Slave to Her Whole Family: The Reborn Eldest Daughter Masters Medicine and Poison

[Reborn for revenge | Poison-wielding healer heroine | Mentor and enemy | Two strong leads locked in a battle of wills | No forgiveness] She was the eldest legitimate daughter of the Grand Secretary, but her stepmother and younger sister found a way to make her a mere concubine's daughter. Blind in her right eye, she became a maid to the heir of a noble house. For three years, she endured people's disdain, did the filthiest work, and bore the most vile accusations. When the heir finally married, his bride was none other than her younger sister. On her wedding night, the bride gave her the agony of poison burning in her gut and the torment of a white silk cord around her neck. Reborn, she was determined to avenge herself! She would repay everyone who had wronged her a hundredfold. She competed in the monthly trials to win a title, then amazed everyone by studying medicine and healing her eye. Using poison, she destroyed the entire family step by step. Yet her “master,” the investigator in the Song Manor murder case, simply turned a blind eye... “Why won't you investigate this to the end?” Song Ling pressed a hairpin to the investigator's neck. “Because... I am not from this country in the first place,” Yan Yi replied with a smile. When they first met, Song Ling and Yan Yi each had their own agenda. Yan Yi: “Since you've become my disciple, you'll have to give me something in exchange.” Song Ling: “What?” The young man said nothing, simply waiting. Two years later, covered in wounds, he stroked Song Ling's bloodstained cheek and said again: “I want you and me to... grow old together in this lifetime.” A foreign crown prince with brilliant medical skills and a clever mind × a noblewoman bent on revenge, shrewd and calculating Master healer × poison healer [I'm a new writer and my writing isn't great. If that's not your thing, please move on. Thanks ❤️ This is a fictional setting!!!!!]