Seo In Guk promised he would celebrate with 15& if they win on a music program.

On April 17th, the three singers guested on the SBS radio show 'Park So Hyun's Love Game'. On air, Seo In Guk looked back on when he was a guest on the same radio show as a contestant on Superstar K'. He commented, "At that time, I hadn't even won first place yet and I wasn't anything, so I didn't even dream of becoming an actor. But now I'm where Park So Hyun said I would be."

15&'s Park Ji Min also shared, "My first performance on radio was on 'Park So Hyun's Love Game'. I'm also where unni said I would be." Park So Hyun laughed as she said, "I have a good eye. I should become a producer now."

Seo In Guk also congratulated 15& on releasing their new single "Somebody" and promised, "If they win #1 on a music program, I'll go on stage and do the wave dance with Park Ji Min and Baek Ye Rin." He also added, "15&'s stage is so refreshing. When I watch them from the side, I want to jump on stage because the song is so good and exciting. "