Actress Kim Jung Eun took part in JYJ's first Korean album title song, "In Heaven".

"In Heaven" is a song written and composed by JYJ's own Kim Jaejoong, where Kim Jung Eun featured on the track to narrate, "sa rang hae (I love you)". Although a small part, Kim Jaejoong decided that the short line must contain the right emotion and told his management that it would be nice if an actress with a nice voice could do it. JYJ's agency, C-JeS Entertainment, spoke on a phone call with 10 Asia, "After we heard Jaejoong's story, we were looking for an actress and actress Kim Jung Eun enthusiastically answered our call. All of JYJ's members were happy and thankful." In addition, it was revealed that it was the decision of JYJ's members to put Junsu in the music video for "In Heaven." JYJ's agency said, "Jaejoong stated that rather than himself being in the music video for the song he made, he preferred Yoochun or Junsu being in it. The decision was made under the agreement of all of the members that Junsu best fit the character of the synopsis." Although Junsu does not have experience in acting in dramas, he has starred in musicals such as "Mozart" and "Tears of Heaven", and has studied acting consistently. Junsu partnered up with actress Song Jihyo as a couple and it is reported that they received good feedback from the crew. JYJ's full music video for "In Heaven" will be revealed on September 15th.