Hi Guys, It's me again. My third post in recommendation forum but don't put me under spam. I just want some recommendation on storyline that I want to watch.
I am looking a drama/movie from any countries where the both leads are together from beginning til end. There won't be any 2nd lead (if there is, only for a while). There could be any sad scene but not because of the third party. 
Example for the drama;
Love O2O, where there was/were 2nd lead but the leads still together. There was also sad scene but not exactly related to the lead's relationship. 

Edited:
Some recommended drama that I've watched
- It's Okay That's Love
- Bromance
- Faith
- Healer
- You're All Surrounded
- Splash Splash Love
- Coffee Prince
- Goblin 
- Arang and the Magistrate
- Blood 
- The K2
- Tomorrow With You
I guess no drama fit the description? or Might be my English problem? :(
Maybe It's Okay That's Love wiil fit to your description.There wasn't any second lead. It was a great k-drama. 
Oh! I didnt think that. Thank you but I've watched it already. 
Bubble Gum _ They've been best friends since forever and also like each other, the only problem the romance starts a little later is bc they're afriad to ruin thefriendship. There sad scenes that have nothing to do with the second lead girl (who discretly like the guy) but with life, work and health.
Bromance
Faith
Healer
You're All Surrounded
Splash Splash Love
Coffee Prince
Goblin
Legend of the Blue Sea
Arang and the Magistrate
Blood
Love Me if You Dare
The K2
Tomorrow With You


Thank You for the recommendation. Will take a look at some drama that I haven't watch yet.

BubbleGum
Legend of Blue Sea
Love me If You Dare
No 2nd lead at all:

Soratobu Kouhoshitsu
Bring It On, Ghost
Oh my ghostess
Descendants of the Sun
Legend of the Blue Sea
Madame Antoine
Mars
Nigeru wa Haji da ga Yaku ni Tatsu
Nodame Cantabile
Oh My Venus
Queen In Hyun's Man
Sekai Ichi Muzukashii Koi
Shopping King Louis
Tatta Hitotsu no Koi


Pretty weak 2nd lead:

The master's sun
From 5 to 9
Flower Boy Next Door
Kill Me, Heal Me
New drama Fight For My Way seems to fit the description.

Other than that, some from my completed list:

Thumping Spike
Warm and Cozy
Just You
Queen Inhyun's Man
I Am Sam
@Wedness Will look up for "I am Sam" Thanks~

@fanitha watched most of it. Will look up for Soratobu Kouhoshitsu , Sekai Ichi Muzukashii Koi and Tatta Hitotsu no Koi. Thank You :)
Thank you for more recommendations. Will look up for the dramas that I have not yet watch~ :D @izzyDramaLover