There was a time when Super Junior went to Japan for a concert. Heechul shared a room with Sungmin, but on the first night, Heechul heard Sungmin snore. So he told Sungmin, “Yah, you were snoring.” Sungmin answered “Ah, hyung, really?”
The following night, Heenim didn’t hear snores anymore. So the next day, he said “Sungmin, I didn’t hear you snore anymore.”
..It was because Sungmin didn’t sleep at all — for Heechul’s sake.