On December 9, IU and Sung Si Kyung released their collaborative track 'First Winter'.
The song was the first one in almost nine years since their first duet song 'It's You' released in 2010.

IU wrote, "The one and only thing I did for this project was suggesting that we should do a Christmas song. It's a good thing I did that, right?"
She cutely added a message to Sung Si Kyung, "Let's take good care of our throats and meet again in 10 years."

To this, IU commented, "Then I'll buy you a cashmere sweater," making their fans smile from ear to ear.

(Credit= 'dlwlrma' 'mayersung' Instagram, '1theK' YouTube)
(SBS Star)