Some shows where I felt happy with the leads chemistry 

1. My Beautiful Gong Shim

2. That man oh soo

3.  Father I'll take care of you (Kim Jae Won and Lee Soo kyoung)

4. Dear Heaven 

5. Father is strange 

6. Whats wrong with secretary Kim (airing)

7. Coffee Prince

8. My daughter Seo Yong

9. Whats up fox?

10. I can hear your voice.

11. Marriage Contract

12. Wonderful days (esp the younger version of the leads)

13. My Girlfriend is a Gumiho

14. The Scholar Who walks the Night

15. Resurrection/Rebirth 

16. Man from.the equator

17. City Hunter

18. Healer

19.Kill me Heal me

20. Chicago Typewriter

21.Judge vs Judge (insanely good in last 2 to 3 eps)

22. Sungkyunwan scandal

23.A hundred year inheritance

24. Yong Pal

25. Who are you? (School 2015) 

26. The Princess Man

27. The innocent man

28. The snow queen

29. Fantastic (had fantastic lead pair chemistry)

30. Angel eyes (the younger version of the  pair was so good)

 OliCT:

Hello guys, I need your recommendations.  I need a drama where the chemistry between the characters are so great that you feel sooo entertained and happy by just seeing them on screen. 

This could be a drama where the chemistry between one of the couples are so electrifying that you ship them like crazy (Ex: "Should we Kiss First?", "I Have a Lover", "Master's Sun").

OR a drama where the chemistry/relationship between the characters are  just so perfect and likeable..it could be just between two characters (Ex: Secret Forest) or between a group of people (Ex: Misaeng, Romantic Doctor Kim, LIVE, A Gentleman's Dignity).

Thank you so much! 

I have only watched kdramas but chinese or japanese dramas are okay too. I have never gotten through the first ep of a japanese or chinese drama.. so yeah if there's a good one I'll give it a try.

Have given my kdrama recommendations in a separate reply. For a Japanese drama, I'll recommend watching "A Hundred Million stars falling from the sky"(would be very different to what you may have ever watched!)

You can also try the Taiwan drama-"The perfect Match" which also has a great lead pair 

Watching "What's wrong with Secretary Kim?" right now and the leads have amazing chemistry.

 OliCT:

Hmm.. I think rather than tension, I like it when you just can't help but smile when you see the characters. I also like it when you emphatize with the characters..as in you like them so much that you don't want them to get hurt; that you just want them to be happy.

I watched King of Dramas already. I liked it haha.

Yaaaaas! You will (definitely) LIKE Last Scandal. Give it 4 episodes, in 2000s kdrama they will establish the foundations in the starting eps. You will like Last Scandal, and that's a promise. ????

As with "ensemble" chemistry, Beethoven Virus.

for me its gotta be

WHY WHY LOVE

DEVIL BESIDE YOU 

rainie yang and mike he is the cutest couple alive TT

It's still ongoing but the chemistry between leads in Come and Hug Me is insane from beginning to end (recent episodes)!

Tomorrow with you, just an amazing chemistry