Mighty Mouth's Sangchu shared the reason why he rejected�Psy's offer to go out for a drink.

On the October 24th episode of MBC's 'Radio Star', Sangchu stated, "There is something I am really sorry to Psy about."

He continued, "There was a song that Psy said he would feature on. Before Psy got this big, he called me to go out drinking with him, but I was really sick so I could not go. This didn't happen once but twice," expressing his regret.

Sangchu went on, "After I got better, I called Psy, but I couldn't get in contact with him. The following week 'Gangnam Style' was released, and it became a massive success."

The Mighty Mouth member also shared that he paid a small fortune to have Yoon Eun Hye feature in his song "I Love You", which rose to the top of the charts and became a #1 hit.

Lee Chang Myung, Defconn, and Solbi also appeared on this episode.