These pictures became the topic among fans (especially DBSK’s). I found these pictures on a lot of fan’s blogs. ^^ They were close. You may knew that K.Will was the vocal coach of their first single “Hug” and also chorus in that song (listen carefully you’ll hear his voice).
There are some more, I think you may didn’t watch these videos on Arirang TV. There are story back then, some part about Rain too. ^^
K.Will – Shopping (English Subbed)