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The idol and former 'Produce 101' contestant took to Yue Hua Project's Instagram to celebrate the occasion with fans. He said, "The end of my adolescence! From here on, the adult Ahn Hyung Seob begins!! I met you all at the end of my adolescence, and I'm thankful to be able to bring it to a close happily~~~~. Please send more of your love in the future."�

Of course, netizens also discovered Ahn Hyung Seob's graduation yearbook photos and couldn't help but notice the idol's signature sass showing through. Check out the photos below!

[#??] ??? ?? ?? ???? ?? ??? ??!! ???? ???? ???? ???, ?? ???? ??? ? ? ??? ??????~~~~~ ???? ?? ??????

A post shared by ??X?? (@yuehua_project) on Feb 2, 2018 at 4:33am PST