You know him as the brusque yet innately sweet character in 'Oh Hae Young Again.'  You know him as the charismatic rapper of Shinhwa.  And you know him as a surprisingly soft-spoken man despite his manly appearance, but what's Eric really like on the set of his drama?

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His co-star Jeon Hye Bin dished in an interview with 'Showbiz Korea' on May 25, stating that he was a funny character in real life.  "Eric has a distinctively mischievous side," she started.  "Because he has a humorous side, laughter never leaves the set of the drama. Also, like somebody who seems cold on the outside but is warm on the inside, he pulls pranks with no expression on his face.  He struck a weird pose all of a sudden on the stage during the press conference, didn't he?  Like that, he does a lot of things that people wouldn't imagine he'd do even though he doesn't look like a funny person, so people get taken aback."

Don't be fooled!  This is one complex, lovable man.