Boom disses Jewelry Yewon on a show. 

On the 27th on SBS radio "Boom's Young Street" part 1, Jewelry's "Superstar" was played. As soon as the song turned on, Boom began getting excited.

He expressed, "This song is so good. It's before Yewon joined the group. Seo In Young, Park Jung Ah, the original members, are the best." The comment indirectly dissed Yewon.

Boom has been on the KBS2 show "Invincible Youth 2." Yewon is also on the show. The two of them have been seen on the show arguing back and forth, which has been a hit among viewers. Boom's unreserved jokes made it beyond the show to his own radio program.

Since Jewelry Park Jung Ah and Seo In Young retired from the group, new members Yewon and Semi have joined.