Que Sera Sera. The lead guy, I can't remember his name though (horrible with names). His character was cocky and blunt. He was sort of a jerk, but at least he said what was what.
My fav out of Hana Kimi was also Nakatsu Shuichi, like you guys
but the last drama i watched was Kpop the ultimate audition, so i think my favorite was probably kang chang min, because i loved his voice