Second 20's

This drama is also Doctor Cha the FL goes back to same college as her son after divorce at age of 38-year-old.

Similar in terms of achieving lost dreams. A women after suffering in life, restart her life, by finishing college and getting a job while struggling in love, life and family.

Navillera, is uncannily similar to this series, as it talks about lost dream, struggle and pressure faced by society, for a crime you were never a culprit of.

Mothers studying at the same school/college as their childrens...

These show have a similar premise of a FL having to give up enrolling into university because of life circumstances, leaving the ML alone after highschool and meeting him up again many years later. The plots do get developed differently though.

In both dramas:
- in highschool the ML had a crush on the FL even if he never confessed;
- ML and FL lose contact after highschool and met much later on;
- ML has now a successful career;
- FL had a promising future when in highschool, but she couldn't pursue her dreams and is now in an unhappy situation;
- ML is quite childish and petty, but genuinely wants the FL to grow into her full potential

Differences:
- ML/FL relationship in highschool is a rivarly in Hello Again! and frienship in Twenty Again;
- in Hello Again! the FL has to give up university due to some family debts. In Twenty Again the FL needs to leave before graduation due to getting pregnant;
- the time jump from highschool to present day is of 10 years in Hello Again! and 20 years in Twenty Again;
- in Twenty Again, the FL is married and has a grown son. Her husband complains about her not being educated enough and wants a divorce, which propels her to enroll in the same university where the ML now teaches;
- in Twenty Again the ML is bitter towards the FL once they meet again due to his first love being completely crushed by her marrying another guy. In Hello Again! the ML is warmer and more supporting towards the FL right away;
- in Hello Again! we have more of an workplace setting, while in Twenty Again we see more of the university life.

Both drama show the lead are giving second chance to go back to university time and do things they wish they have done at college. Eventhough the plot of the story not the same but the vibe they give about rediscovery own self during youth time is the same.

The grown up now and the younder adolescent, the friendships, the love, the fun...

Takasaka Aoi lived happily with his wife, Mitsuki, and their son Ren. But one day, during a medical examination, he was told he had only three months to live. Encouraged by his beloved wife, Aoi decided to fight the disease. But when Aoi left, Mitsuki took out her smartphone and made a call. "Ken-chan. Aoi-kun is really going to die!" Mitsuki's true nature gradually becomes clear. With only three months to spare, Aoi must uncover Mitsuki's true identity in order to protect Ren!

The guy's character frequently offers his help and care for the girl. Both drama was so heartwarming. The guy feels sad for the girl for her misfortune, and tries to make her days better. Both possesses slice of life kind of drama which are relatable.

The romance and comedy is just fantastic.

I would rewatch these two!

After receiving a terminal diagnosis, a devoted husband discovers his wife’s affair. With little time left and his son’s future at stake, he embarks on a relentless quest for revenge that will change their family forever.

There's no time travel here,but the heroine attends college again and also meets the hero again. The male lead's first love is heroine. The heroine is initially married and divorced by the second male lead.

it is the same but just the Korean adaptation, which is also really good and I heavily recommend to watch.

It's not because of the stories but impressions that give you these dramas are very much alike. Just normal, simple stories. No melodrama, no ridiculously vicious characters, no disasters that come to main character one after another. Watching these dramas will make you smile and laugh a little, sometimes little sad. Light and bright plots about real life problems.

Both dramas deal with the female lead growing into herself/finding herself. Also, in both, the female leads have to deal with a hostile working/school atmosphere, are faced with being older than everyone else and have family that doesn't support her dream.
The male leads in both are sweet and funny, not like the usual jerk leads. Finally, both dramas are light and funny, with a lot of heartwarming moments.

Both shows are extremely similar.
-Both have our female lead getting back on her life after losing their status and value.

-Both Female lead divorces their husbands in the course of the show.

-Both Female lead fall in love again with a different man
QOR (2nd lead chaebol PSH, who becomes the main lead after a few episodes in the beginning) and in

20 again (her childhood friend whose first love is the main female lead, he is the main lead from the beginning).

-Both shows have great romances and comedy.

-Both main lead(PSH & LSY) are so much in love with the female lead and have great character development.

-Both husbands are very much not likable.
Husbands from 20 again is a bigger jerk.

Both stories are about finding happiness again and their journey of self discovery. Both have several inspiring messages like it's never too late to be happy and we should love ourselves. Both have funny moments and more sad and tense moments, but overall they are dramas that make you feel good.