From this past March 30-31, singer Kim Jong Kook held his first domestic solo concert in approximately 9 years at Ewha Women's University's Samsung Hall!

Particular on the first day of the two-day concert, Kim Jong Kook's fellow 'Running Man' cast members Yoo Jae Suk, Lee Kwang Soo, and Jeon So Min were spotted in attendance in the middle of the crowd. Another 'Running Man' cast member Yang Se Chan was the special guest of the concert. 

So among the 'Running Man' cast members mentioned above, which one ended up having the most fun out of everyone there combined - even Kim Jong Kook himself?

It was the never-tiring energizer MC, the nation's MC Yoo Jae Suk! Netizens commented, "Kwang Soo was embarrassed kekekeke", "Is it a service at the church of Yoo kekekeke", "Yoo Jae Suk-nim needs to hold a solo concert of his own!", "He's the fanclub president kekekeke", "I wanna have fun at a concert with Yoo Jae Suk too!", and more!

The MC was also called out for a special solo(?) by Kim Jong Kook, which you can check out below!