Today marked 2PM and 2NE1's appearance on the latest episode of 'Running Man', and interest naturally shifted to Nichkhun and his recent dating announcement with Girls' Generation's Tiffany!

With Yoo Jae Suk being his usual prying self, he didn't hesitate to set his sights on Nichkhun.�

"You've been on this show near 10 times," he told him. "We're doing well, and you're doing well too," he said, referring to his happy dating life. "How long have you two been dating?" he asked.

"We're very happy," he answered. "Thank you!"

"If you're happy, that's all that matters," MC Yoo replied. "What is she doing today?" he continued.

Thinking he was referring to Taecyeon, Nichkhun answered, "Filming a drama".

Frustrated by his answers, Yoo Jae Suk decided to go for the jugular. "Tiffany! Tiffany!" he asked point-blank. "What is she doing?"

Finally catching on, Nichkhun replied, "She's resting. She's sleeping".

Check out the clip below!

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