The Young Lady's Personal Medicine Immortal

My master sold me to the Qin family to settle a three-hundred-million debt. From then on, I became the personal doctor of an icy heiress. One needle saves a life, two take one, and three change fate. What they don't know is that I'm about to die too. I have only eight years left. Want to live? Find the nine flames of life. The King of Hell says I must die at midnight, but I'll make sure I live another thirty years.