Both are historical dramas that involve a power struggle over the throne and a love triangle between two royal brothers. In both, the heir to the throne is presumed dead when young and returns, and the other brother, now on the throne, attempts to kill him. Both FLs come from a powerful family but are caught in the middle of their love for the ML and friendship/brother-like relationship with the SML.

Both have a similar vibe and cover a similar period of history, as the people struggle with the Japanese occupation and then adapting to American ways of life. Both FLs are similar in personality - young, but very strong and determined.

Similar setting, both portray the struggle and courage of the people against the Japanese occupation. One has fantasy elements, while the other is realistic.

Both FLs come from the modern day real world into a historical world where they at one point are a servant, and at another pose as a man/are in a man's body. Both MLs are emperors who fall deeply in love with the FL, but realize she must return to the real world.

Both FLs pretend to be eunuchs to stay by the emperor's/king's side. Both MLs have an initially cold personality but are very loving, both FLs are high-spirited.

Both are mini dramas in which the FL enters a fictional world in which she must repeatedly attempt to assassin the ML in order to finish the story and go home.

Both are mini dramas in which the FL enters a fictional world in which she must repeatedly attempt to assassin the ML in order to finish the story and go home.

Both are mini dramas in which the FL is betrayed and returns for revenge by becoming a concubine of a powerful older man, becoming entangled with the ML, that man's son. Both are Republican Era set mini dramas.

Both are mini dramas in which the FL is betrayed and returns for revenge by becoming a concubine of a powerful older man, reuniting with the ML, that man's son, who she loved years ago. Both are Republican Era set mini dramas.

Both are mini dramas in which the FL is betrayed and returns for revenge by becoming a concubine of a powerful older man, reuniting with the ML, that man's son, who she loved years ago. Both are Republican Era set mini dramas.

Both are mini dramas in which the FL is betrayed and returns for revenge against the man she once loved by marrying his father/father-in law.

Both are historical dramas in which the FL is an unfavored identical twin who ends up swapping identities with her dead sister and marrying the ML.