It's a slow-paced period romance, some people won't have the patience to watch it, but it has interesting and somewhat taboo themes that are treated lightly.
Luo Shen Yuan and Luo Yi Ning are raised as siblings, children of the same father, which already generates a discussion about possible incest. After a few years apart, Yi Ning returns to the Luo residence and the two, now adults, are one and the same. There is a mystery surrounding Yi Ning's mother. Shen Yuan discovers that they are not blood siblings, to his relief, since he is already head over heels for his "sister". There is fighting, competition between the family, imperial competition, revenge, everything a historical romance has to offer. The second couple is the cousin of the two protagonists with the Sixth Uncle, brother of the Lady of the house, the wife of the main couple's father. Although there is no blood relationship in the second couple, it is also a taboo subject. They are cute and you root for them too. The ending is super happy.