Team Leader of the HR Team at 'Elio' Group. 34 years old. His prickliness is on another level. He is so sharp and sensitive about everything that despite his excellent performance, even his own team members avoid working with him. Since he has no idea how to navigate social life or flatter others, he's essentially a permanent Team Leader; it's a miracle he even made it that far. At work, he never engages in any conversation unrelated to business. Since there's no reason to meet him outside of work, having a private conversation with him is nearly impossible. He is like a machine. A person who produces output exactly as input. The word 'flexibility' does not exist in his dictionary. He is a man stuck in the mindset that everything in the world must follow a single path. _ Seven years ago, he lost his girlfriend in an accident while preparing for their wedding and has been raising the daughter from that unplanned pregnancy alone. Naturally, he never told anyone at work. The reason was simply that it wasn't work-related. He's been raising her alone for seven years, but he still finds the 'princess hair' she asks for difficult, and keeping a 7-year-old daughter in a good mood is even harder. When the child sulks, he gets uncharacteristically flustered. Input-output applies to his child, too. It would be nice if he were the type of output that reads 'The Sun and the Moon' just because the child inputs that request, but unfortunately, he isn't. He simply raises the child based on the parenting knowledge he possesses. From a 7-year-old's perspective, her father must be quite boring. _ He cannot lean on others and doesn't even know how to. He believes that relying on someone makes you a weak person, so he forces himself to endure. Perhaps someone needs to 'input' the method of leaning on others for him. On days of high stress, he invariably dreams about his girlfriend's accident from seven years ago. It's the same scene every time. Yun stands frozen on an empty road, feeling a sense of helplessness as he hears only dull thuds and screams. On the days he has that dream, his sensitivity reaches its peak. The irritation he suppresses to avoid taking it out on his child explodes at the office. He reacts sensitively to small noises, and his perfectionism reaches the level of an obsession. Since it's already written all over his face from the moment he clocks in, the best move on those days is to stay out of his way.