I just love Jaejoong's voice, there's this distinct thing in it that will pull you in. In this song, JJ and Yoochun's voices blended so well it almost made my ears cry in happiness (lol). I will never get tired listening to this for it gives me this warm and fuzzy feeling like there's nothing to worry about. And I absolutely adore their smiles and the look they gave each other =P
p.s. Almost all of Dong Bang's Japanese songs are fabulous.