Wow, a lot of dramas pierced my heart deeply.
Among few.. LIE TO ME (especially the moment when the female main lead got into a car and cried while driving - that was so real) MY LOVE FROM STARS (the last 2 episodes drained me out from not only tears but also all emotions, I cried so much if someone would see me they would think someone died) SECRET (a lot of moments that shattered my soul making me rewatch this drama over and over again because of the beautiful acting mean leads did) SCENT OF A WOMAN (bittersweet drama) THAT WINTER THE WIND BLEW, HOTEL KING, MASK, etc... Strangely, for me LIE TO ME still remains on the top of the list and no matter how many times I watch that one, every time the chemistry and love between those two is so real I can feel it through the screen.
It's too hard to pick just one!

Drama romances that I will rewatch just for feels time and time again:
Falling for Innocence
Second time twenty years old
kill me, heal me
Endless love (second lead syndrome!)


Oldies but very intense romances/plots : What happened in Bali , Que Sera Sera (Not your average K-dramas..talk about emotional rollercoaster endings..)
Most Emotions  means = Makes me care about the characters .. ... various feelings  that I want to re-experience! ... 
These did all that:

The Princess' Man
Nirvana in Fire
East of Eden
Chuno
Sound of the Desert
Empress Ki

I am sorry to include japanese dramas as well (mostly are Koreans Dramas)

Healer (Rush of Emotions)
Empress Ki (the strong feelings the leads had for each other, I still feel it when thinking about them - Extreme Love and Fear from losing )
Two Weeks (I shouldn't ever forget her smiles at his father, full of courage and strength) It's Okay That is Love - just by watching you can understand the emotions you will be left with .
Six Flying Dragon - for the first time I felt the pain of loneliness- that really hit me and became sad (Traitors aren't necessarily the bad guys).
Lipstick (1999) - Its so special the feelings from this older J-Drama , Little Spoiler - beautiful feeling I was left when these girls became more and more friendly with each other)
1 Litre of Tears - (Feeling of gratefulness for our lives - it's so precious yet we might not be aware of it) Mask - (Someone's Trust in you can make life so elegant and push you through any hard time)
Orthros no Inu -( I was left with a really confused(hate) feeling about human's expectation from individuals. just do what your inner self tells you to do and don't bother about each other people.
Remember – War of the Son ( another drama that makes you feel the pain of loneliness at the end of story ) Thank You (another drama that made me be grateful about everything I got).
White Christmas (Feelings of fear that humans are so frighting creatures). I was reminded of an anime called Death Parade which is kind of similar to the drama for those interested.
Secret with Ji Sung
You Came From the Stars
That Winter, The Wind Blows
Scent of a Woman
Hotel King
Mask
Innocent Man
I Miss You / Missing You
Can You Hear My Heart?
Heart To Heart
Wife's Credentials
Bad Guy
Master' Sun
parts of Secret Garden
parts of Lie to Me 
parts of Marriage Contract
parts of Faded To Love You

All above left a scar on my soul. Memorable, plus If I cry on them or the ending is not what would expect, they stay in my mind. I ether re-watch it, or never touch it again because of the mark they left on me. 
I love mature dramas that are memorable and that I learn from. I don't care for cliche dramas too much. Secret with Ji Sung was one of those that I would watch over and over again. Hotel King and Mask, That Winter, The Winter Blows were unique and I simply loved them too. Wife's Credentials - very mature and very real. Lie to Me - my favorite of all times because of the real chemistry between leads, etc.



Mother, it's the one I'm currently watching, the strongest emotion is sadness, I like cry every epiosode ;_; but there are other emotions like happiness
Reply 1988

I cried in so many episodes ;;___;;
Sincerely loved it
LONG LOVE LETTER... HONG GIL DONG...KILL ME, HEAL ME...CAN YOU HEAR MY HEART...UGLY ALERT..TONBI...TENNO no RYORIBAN...MOTHER (J)

JAM LOEY RAK (so many emotions with this one)
So there are dramas that are exciting and amazing and get you at the edge of your seat. And then there are dramas that are really uplifiting. And then there are dramas that do all of the above and REALLY touch upon your heart. Those are just a handful for me. 

1. It's Okay, That's Love
2. Good Doctor
3. Descendants of the Sun

But I also have to mention I Remember you, You who came from the stars, Queen InHyun's man, City Hunter and Oh My Venus. They touched me all in different ways and left a long-lasting impression. 
Marriage contract
Queen Inhyun's Man
Empress Ki 
Valid Love
Autumn Tale
Nagareboshi
Cain and Abel
If in Love Like Them
The Snow Queen
I Miss You 
Kill Me, Heal Me
The Spring Day of My Life
The Princess' Man and Kill me, Heal me
Mostly sageuks can make me feel all kind of emotions ^^

Empress Ki
Queen Seon Duk
Six Flying Dragons 
The Princess' Man
Kill Me Heal Me
The Bridal Mask
Healer
1. Healer
2. It's okay, that's love
3. Fated to love you
4. Heartstrings
5. Missing you
6. Angry Mom
7. Rooftop prince
8. Kill me, heal me
birth secret 
secret
Lee Jun Kai
the king 2 hearts 
forget the rest..... i could really teared up T.T