F.T. Island's Hongki revealed why he and EXO's D.O were so nervous while singing the congratulatory song at Park Shin Hye and Choi Tae Joon's wedding.

On the June 8 KST broadcast of MBC's 'Radio Star', musical director Kim Moon Jung, actress Seo Yi Sook, trot singer Song Ga In, and F.T. Island's Hongki appeared as guests. This particular episode had a special theme titled "The Fiery Priest", gathering attention.

On this day, Hongki revealed a behind story from Park Shin Hye and Choi Tae Joon's wedding, confessing that he and EXO's D.O, who sang the congratulatory song for the couple, were very nervous on this day. Hongki stated that the wedding guests were all top stars to the point that the wedding ceremony felt more like an award ceremony. Further, Hongki was the first in line to sing, which increased his feelings of nervousness. Hongki then stated, "D.O, who was up next, was shaking. Thanks to him, I was able to relax a bit."

Watch the clip from 'Radio Star' above!