The ONO Entertainment trainee gained tremendous attention and love after the contestants very first stage of ''Pick Me'' on 'M Countdown'. His ending moment went viral and he gained the nickname 'Ending Fairy'.

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At the press conference for the show on April 3, Ahn PD revealed, "Some people asked if I cast Jang Moon Bok (to gain attention for the show) but I really didn't. I confirmed his desires to become an idol and that's how he came on the show. I didn't expect this much popularity for Jang Moon Bok. I'm surprised by it every day."

He also shared a comment about 'Ending Fairy'. Ahn PD said, "It's a coincidence how he became the 'Ending Fairy'. As the trainer said, he was originally in the 'F' ranking but he worked really hard. I couldn't resist capturing him for the ending. I'm also very curious as to how he'll grow from now on."

The first episode of 'Produce 101' season 2 is airing on April 7.