Singer/actress IU and singer Sung Si Kyung celebrated the groundbreaking success of their new duet song 'First Winter'.
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.
On the same day, IU took her Instagram to share her words of gratitude to all the listeners who loved the new song.
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."
Sung Si Kyung also wrote a message to his fans, and added some hashtags that says, 'Thank you', 'It's all thanks to IU', 'I should by her a rose gold necklace'.
To this, IU commented, "Then I'll buy you a cashmere sweater," making their fans smile from ear to ear.
You can watch IU and Sung Si Kyung's 'First Winter' music video below:
(Credit= 'dlwlrma' 'mayersung' Instagram, '1theK' YouTube)