Any where the male lead loves the female lead while she loves the other guy who is his brother. Eventually she falls for the male lead and they end up together.

Definetly Moon Lovers Scarlet Heart Ryeo....It's not a happy ending,but it's sooooo worth it tho:D Beautiful Days is a very good one...It's too underrated tho,don't know why-.-

likit fah cha ta din

uhm.. this formula though not there the entire time... Noble My Love?

The Imperial Doctress

Lost Love in Times

Queen for Seven Days

reply 1997

scarlet heart - moon lovers ryeo

A Girl and Three Sweethearts

Palace the lock heart jade

Scarlet heart (cdrama) 

scarlet heart ryeo

 a girl and three sweethearts 

20th century boy and girl(airing,  not sure but its going in this direction) 

 reply 1997 

five fingers

Why why love 

the eternal love

 goong

 cinderella and the four knights

Why why love

Snow white

She is Nineteen 

Weightlifting fairy

Gomenne aishiteru / I'm sorry I love you

The Eternal Love - She marries the 8th Prince as it was the emperor fathers decree but she really loves the crown prince. After time together, she eventually falls in love with the 8th prince. It's a good drama ... wasn't sure of the plot at first  but i did really enjoy it in the end.

I've watched most of the above mentions and second their notions!  Ones I personally liked the best are:

  1. I *just* watched Reply 1997 for the first time and have to say that was a really good story.  Intriguing tale that gets knee deep into what one bro will sacrific for another.   
  2. I'm Sorry I Love You was very emotional story on many levels.   Worth the number of eps.
  3. Queen for 7 Days is so intense and dramatic with 2 amazing lead bros....
  4. Scarlet Heart Ryeo was a great story and lots of eye candy.