I Became a Blood Servant of Sister Yu's Blood Clan

Zuting Star is a planet with strict hierarchies. The upper-class and middle-class people have the qualifications to practice, while the lower-class people can only be mortals. The lower class is divided into three classes: the first class is the rich, the second class is the common people, and the third class is the poor, thieves, and outlaws. Luo Cheng, a low-class man whose family was ruined by the Black Dragon Gang, was only a twelve-year-old boy, but he spent three years getting revenge. After taking revenge, he thought his life was over, but he didn't expect to meet a royal sister of the blood clan...