I know it's pretty common in dramaland- But I've seen so many already. I need to be reminded of more~^^
Only Korean plz. I'm trying to learn Korean, so watching a different language throws me off. =P 
Please please please♥ Thank you

Anything pretend relationships, contract relationships, etc ♥

Maybe you could tell us which dramas you have already seen? :D I really like pretend relationship trope and seeing that you saw way more dramas than i did, i bet you know some that i don't :D.

Anyways, i didnt find in your list Mary stayed out all night. If i should be objective, i would say that it was pretty average drama BUT! for some reason i really liked it. Next one is My name is Kim Sam Soon which i haven't seen but i think it has pretend relationship too, (it was probably recommended here ;))
Okay thank you!! =)
Ones I've seen with it:
Goong (To a certain degree it has it)
Marriage Contract
Fated to Love You (To a certain degree again)
Creating Destiny
My Girl
Mask
Madame Antoine (in a way?)
That Winter, The Wind Blows
Lie to Me
Prime Minister and I
Full House
Please Come Back, Mister (Sorta)
The Eccentric Daughter-in-Law

Maybe more Idk... Oh ones I'm currently watching
Another Miss Oh (not much - but still there)
Que Sera Sera
- Vampire Flower: web drama, they kind of formed a contract, borderline contract relationship
- Bride of the century: in a pre-marriage relationship, kinda pretend
- Master's sun: they needed each other for different purposes, so kind of a contract relationship
- Innocent man: the man used the girl for revenge, so kind of pretend relationship

I second My Name is Kim Sam Soon--I cannot recommend that drama enough!  You might also try Noble, My Love; Marriage, Not Dating; and  King Flower (aka Substitute Princess).
The best I have have seen so far is ''Marriage not Dating''. 
Delighful Girl Choon Hyang
Marriage not dating
Mary stayed out all night
1% of anything
This is a helpful article with a ton of recommendations. I'd also suggest Dalja's Spring.
This one is a little old but it was really good, Wonderful Life (2005) korean drama ( there's a few under this name)
You will definitely love these! The guy's jealousy is so cute and the kisses are so good:

Marriage not dating
1% of something (2016 version)

PS: I need contracted marriage dramas as well but after the year of 2013