When she was a child, she came with her father to live in a remote town in York, England. She didn't know why they came here. Until one day, a group of people in religious robes suddenly burst in and killed both her and her father. However, the oozing blood summoned Count Valade, who had a contract with her, and he saved her. Later, Yu Ruo was rushed to the hospital for emergency treatment. This was the first time she saw Count Valade, who had a contract with her and had saved her. She also learned from a police officer named Chris that it was an organization called the Blood Raven that had killed her father.