Kim Gu Ra does it again, letting his mouth run afoul on MBC's 'Radio Star' on July 15 with members of Super Junior as guests.  

Right off the bat, he brought up what could be a sensitive topic for the boys when they appeared on set for the episode's opening.  He asked, "Today is a Super Junior special, so why is Kangin not here?"  Kyuhyun replied, "Kangin and Ryeowook were unable to come out because this overlapped with programs they appear on." 

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Yoon Jong Shin commented, "Even when Kangin appears alone, everything he has to say takes up one episode," making everyone laugh.  However, at this point, Kim Gu Ra unnecessarily added, "And Sungmin went to the military and Kim Ki Bum and Hangeng left the group," raising eyebrows while the guests laughed it off.

Heechul stood up to look at Kim Gu Ra better and said lightheartedly, thanks to his easygoing personality, "Let's stop please," making everyone laugh again.