Brother

"I'm sorry to have called you here like this." Ji-Won said, brushing a hand over the back of his head. "They asked me for a family member and I didn't know who else to call."

"It's alright. Thank you very much for calling me." Min-Jun replied, staring at the man in front of him with an intense gaze.

The moment he arrived at the hospital, Min-Jun saw the worry in Ji-Won's eyes. It made him think that perhaps this man cared about his sister more than just a boss caring for his employee.

The look on Ji-Won's face, the quivering of his eyes, as well as the rumpled state of his attire, they all pointed towards something more than just a simple work relationship. 

It seemed similar to the way a man would act when the woman he liked is hurt.