Personality. Yoo Joonghyuk was designed as someone 'tougher in body and nobler in heart than any creature in this world'. He is resolute and determined, aiming to accomplish his goals no matter cost, in particular when aiming for the end of the scenarios.he is cold and serious.Yoo Joonghyuk is normally very confident in his abilities, never backing down from a challenge and typically cutting down his enemies with ease. He is extremely talented in various areas, befitting of his status, serious