Second Lead Syndrome Kdramas

1. Heo Yeon Woo & Yang Myung

2. Lee Hwon & Bo Kyung

(preferred also the young cast to the adults)

1. Junse and Eunsung

2. Seungmi & Hwan

I also feel more for the second leads than the mains. Maybe it has something to do with their actors being my biases out of the 4 leads, plus loving them so much in Painter of the Wind (drama that aired the year before this was shown) that it hurts so much that the show's main goal was for them to leave so the main couple are together.

=> Cha Cheonsu a& Dong Yi

strongly influenced by Brilliant Legacy. King and Dong Yi are cute though but I would have enjoyed them more together had Bae Soo Bin played the king or he's not playing the second lead. 

1. Soseono and Wootae

2. Jumong and Yesoya

I love Soseono bodyguard loyalty and love for her. I also love Jumong with the woman he married, I love how devoted she is to him and his mother. I do enjoy the main  leads together, but they have different destinies and different people to take care of.  I also see them as leading their own factions, hence the need to be separate. 

1. Yong and Bongsoon

2. Eunchae and Shihoo

The main couple have some cute scenes. But I feel that the second girl is more suited to the male lead since she knows more of the real him and enjoys his playful personality more. The second male lead suits the prim and proper female lead more. It doesn't help that the main couple reminds me of the OTP in Moon Sun, hence an additional reason to ship them with the second leads.