Nope. No.1 is definitely Kim Tan & Cha Eun Sang. For me, the storyline of The Heirs is outstanding, great OST(s) & most ed couple of all time.

I don't know about you guys, but my most fav is The Heirs. Watched it 12 times because Park Shin Hye & him was the best couple.

Very subjective review. My personal fav romantic k dramas are The Heirs, My Roomate is a Gomiho, Lovely Runner, My Secret Romance, Scarlet Heart & Business Proposal.