With the next episode of KBS 2TV's 'The Unit' airing on December 23, a short preview of the contestants was shown consisting of Jun crying on stage while performing "Butterfly".

Regarding this, the singer said, "I tried my best not to cry. Even while I was practicing though, I felt sad and shed tears. I wrote the rap lyrics on my own, and I thought about my trainee days. It was just overwhelming to stand on stage again and sing. I felt so grateful."

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Onto the reason why he cried on stage, Jun commented, "I cried because the hyungs who got eliminated came to see the performance. The stage light was directed at me and I saw them sitting in the front row. They cheered for me by holding up my name tag. I think it hit me then. I still feel like crying just by thinking about it."

Viewers can watch the full episode of Jun's emotional performance on December 23 at 10:45 pm KST.