As if to thank fan for her win at the '2014 MAMA', IU postato on her Twitter, "I'm happy. It's all thanks to you. This is a present." She then provided the link to the audio heard above, which avid fan of the singer may recognize it to be the full version of the precedente snippet she let fan hear on a fan community page.
IU, of course, wrote and composed the song herself, so make sure to give it a listen above!
(link)