Korea's top female idol groups Wonder Girls and�Orange Caramel will be making a special guest appearance at K.Will's upcoming Christmas concert. This will be the third annual Christmas concert put on by K.Will, which has proved to be quite popular. After selling out both shows for the December 24th and 25th, another show for the 23rd was added. The singer, who has captivated viewers with his live performances on 'Immortal Song 2', will showcase his various charms on stage at his 'This is K.Will' concert. The addition of Wonder Girls and Orange Caramel has increased fans' expectations for the show, and K.Will revealed that an additional surprise guest is lined up to join him on stage on the 24th. K.Will's agency Starship Entertainment remarked, "We have received a flood of requests to open up another performance on the 23rd, and we are so thankful as it looks like that show will be a sold out one as well. We will deliver a show as great as your expectations, and our entire staff is working hard preparing for the concert." In related news, the singer is exuding strong stage presence on 'Immortal Song 2' and will be actively promoting on various television programs.