Actor Kim Woo Bin revealed a funny side that he's never revealed before.

On SBS "Running Man" aired on December 14, Kim Woo Bin appeared as one of the guests.

For the blinking game, Yoo Jae Suk and Ji Suk Jin drew over their faces and put tape around their head, shocking the viewers with their funny looks.

Kim Woo Bin's competitor was Gary. Kim Woo Bin put tape around his head and said, "Pull my mouth back too," showing great competitiveness. The members were worried for Kim Woo Bin, saying, "Stop doing that to the handsome boy."

And the game began and Kim Woo Bin pulled his mouth all the way back with the tape and rolled his eyes back, making the funniest face possible.