Seventeen's Seungkwan appeared on KBS 2TV's 'Hello' on December 5 and revealed a strange thing he can't do!

On this day, he aired a grievance, stating, "I can't sit cross legged. My pelvis won't open. I went to the orthopedist and was told that it would always be like that."  The show has the guests and MCs sitting cross legged on pillows, but the MCs told him to stretch his legs and sit comfortably.

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Seeing him sit like that, Shin Dong Yup said, "I'm envious. I should've done that, too," making everyone laugh.