The female lead has a child, she was married and got cheated. The male lead is younger than the female lead.

Older Woman/Younger Man romance. The female lead is strong and the male lead is bright person. The male leads return from abroad in both. The male lead loves the female lead since childhood. Both female leads work in office (male lead as well but not in the same office), side characters are supportive.

Older Woman/Younger Man romance. The male lead is nice person and the female is strong and nice; male chases the female first; in both dramas, the ML and the FL work in office (office romance); main leads are neighbors , they live in the same apartment buildings.

Older woman/Younger Man romance, The female lead is strong in both. The male leads return from abroad only for the FL, both male leads love the female leads since childhood. Male lead chases the Female lead first. The side characters are supportive and funny.

Leads were childhood friends and often used to visit each other's house. Male Leads went to study abroad and returns after few years. Both male leads love the Female lead first.

In both drama, the male main lead is doctor, the female lead is cheerful. Both are rom - com with a lot of fluff. Both have secondary couples.

Story between two best friends and their strong friendship. In both, the FLs knew each other from their childhood. Despite their hate, misunderstandings, they both love (not romantically) and care for each other so much.

Similarities :
- Both dramas show us main characters' high school life to adult life.
- a group of 5 friends.
- neighbors.
- childhood friends.

- ML died unexpectedly.
- Travelling through time and space.
- ML was in love with the FL secretly for 10 years in TM19YO and 11 years in SFOT.
- Both FL regretted later that she never noticed the ML in the past.
- After going back to the past, FL tried to fix/make up all of his regrets.

ML is a fictional character of the FL's novel/diary in both dramas. One day, the ML arrives in front of the FL and they started to live in the same apartment.

The synopsis is exactly the same for both.
The ML is a fictional character of the FL's story. He is a villain in that story, one day he comes to her house and forces her to let him live with her. His arrival makes her life miserable. Despite the many things that happened, he is gradually moved by her warm spirit and unexpectedly falling in love with her without realizing it.

In both dramas, the ML is a fictional character of the FL's diary/novel. After ML comes to the real world, they started to live in the same apartment.