I heard Young K appeared in both seasons 1 and 2 of 'Dream High'! I just found that out haha.

Young K revealed that some of the trainees at the time were selected to participate as backup dancers on the 'Dream High' stage. Jang Wooyoung confessed that he was unaware that Young K was among the trainees who stood on stage with him at the time.
The even more surprising fact is that Young K appeared in both Season 1 and Season 2 of 'Dream High'.
I just found that out too, haha.