Both series feature a young female character who ends up meeting a powerful older man and developing a unique relationship with him. Both women develop unrequited love for the elusive man and go through many trials because of their love.

Both dramas are about a teacher and student that somehow end up living together and must keep it a secret from others. They begin to develop feelings for each other.

Both series heavily feature medical aspects with there being a younger woman who enters the field to get closer to an older man that she loves.

Both series take place in hospitals with the main character pursing a career in medicine to aid/get closer to their crush.

Both shows showcase people from different countries and their opinions and experiences on topics based on their cultures and how they view and differ from Korean culture.

Both dramas are about one of the leads falling in love with the other when they were younger and being reunited later on after the female lead has gained/lost weight. Her changed appearance also leads to mistaken identity/not remembering the other from before.

Both series are about an older office lady going abroad and meeting a younger man. Both of the women initially lie at the start of their relationships.

Both films focus on the relationship between an older married woman and a young university student. Art is also central to the characters.

Both dramas are about a career woman in her 30s who ends up in a relationship with a young co-worker 10 years her junior.

Both titles focus on a romance between first cousins and how they navigate their feelings for each other.

Both series focus on a forbidden romance between family members. Mistu no Aji features a uncle and niece who have fallen in love while 90 Days of Love they are first cousins.

Both series focus a smart female character who hides her intelligence to protect and enable her to maneuver in the restrictive and dangerous role women had in historical china.