Singer Ailee presents a warm year-end with a season song.

The image of Ailee's "Sweater" plan was unveiled on Dec. 8 through the official SNS channel of her agency Rocket3 Entertainment.

According to the plan, Ailee will start with a special image of "Sweater" on Dec. 9, followed by a teaser image on Dec. 10, a cover image on Dec. 11, a single release of "Sweater" on Dec. 12, and a music video in sequence.

In particular, the image that was released with snowballs and scattered snow are raising questions about the winter concept and new songs that Ailee will show in "Sweater."

Ailee, who is currently meeting fans from all over the country with the national tour concert "I AM: RE-BORN," even delivered news of the new song's release and promised to continue to be with fans at the end of 2019.

Ailee released "Sweater" on various music sites on Dec. 12, in line with "12 Day" built by fans.