Heechul is known for, among other things, being popular and well-connected within the entertainment industry.
So it comes as no surprise that his birthday was widely celebrated by his friends.
What was a surprise, however, was how Heechul actually spent part of his birthday.
Heechul happened to be filming the TV show Idol School on his birthday, meaning he spent his birthday with 41 “school girls!”
During filming, the girls even sang a “happy birthday” song to Heechul, which he posted on Instagram.
Heechul captioned the clip with, “#IdolSchool #Touched #IWillBecomeAWarmTeacherWhoDoesntWaver #GTO #GTH #GreatTeacherHEENIM“
Idol School will begin broadcast on Thursdays at 9:30 KST on July 13 with Heechul as the homeroom teacher.