Since this is Vietsub... I'll kinda translate for u guys... when Young Saeng tried to climb on that high place... Hyun Joong ran in and grabbed his legs... scold Saengie, "You gotta be careful... It's very high... What  if the wind blow you off?"... the second part is... Uploader's note, "I swear they secretly held each other hand"... okay idk if it's true but in my eyes... it really looks like it... aigoo these two... can't get enough...

http://www.youtube.com/watch?v=ie_LBW2Ft8Q