On the 13th,�Leeteuk posted a photo on his twitter saying, "An outfit that reveals my back... You didn't know right? Keke. I'm going to delete it soon so look quick keke".

Super Junior's leader reveals his bare back and muscles, flaunting his surprisingly muscular build.

Netizens replied to the photo saying, "After putting in all that effort into working out... you're awesome", "Surprisingly sexy", "They're really unexpected back muscles", and more.

Meanwhile, Super Junior is currently actively promoting their 6th repackaged�album's�title song "SPY".

Source:�Leeteuk's Twitter