Happy Pledis purpose is to make a warm atmosphere for the cold winter, some of the album proceeds will be donated to UNICEF, to help many children.

All of Pledis Entertainment artists are going to be in the said album, After School, Son Dam Bi, Pledis Boys, Ara and Hyerim who is being prepared to debut in 2012, is already calling a lot of attention.

The album consist of many genres.

it is said that the composer for songs such as 'Melody 9' 'Good Day' and 'Abracadabra' that are popular hits in Korea composed the songs in the album. The title track is "Love Letter".

Love Letter is a dance song with shy lyrics and heart warming with joyful melodies and wintery atmosphere. the song will show a close relationship between Son Dam Bi, After School, and also Pledis Boys.

meanwhile '겨울 이야기' by Son Dam Bi, Kahi and Jungah will show exotic charms which is expected to attract many fans. there is also Orange Caramel with '어떤가요' and After School's 'LOVE LOVE LOVE Remix' which is more colorful and a bit faster than the original version.