The Evil Lord's Wife Has Spirit Blood

In her past life, Michelle was an ordinary doctor who worked in a small hospital, but once in a while, a strange envelope would arrive at her apartment and she would take up a weaon and turn into a deadly assassin known for her stealthiness. But being a top assassin, Michelle had many enemies and ended up dying, only to wake up in the body of Michelle Grace, a pampered young miss in a world similar to ancient dynasties, except that cultivation existed there. Not everyone could cultivate, but Michelle Grace could.

The original Michelle Grace was engaged to the Crown Prince, and he killed her before Michelle took over the body, so after making a deal with Michelle Grace's father, the Archduke, Michelle took on the name Grace and started a revenge plan on the Crown Prince, his lover, his mistress and his father, the Emperor.

A bit troublesome: Michelle gained the attention of two men who together were the Dark Lord. They were horrifyingly powerful, so Michelle had to be careful around them. Luckily, they didn't have in their plans harming her, as they were intrigued by her constitution. Michelle possessed a rare blood, which they could use.